Tag Archives: eco-heating

Cool fireplace design

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On the theme of substituting alternative wall finishes for plaster here is a large brick fireplace that looks absolutely stunning with a wood burning stove and adds a bit of ‘wow’ to any room. Shown here, part finished, the brick construction is a structural part of the house with the essential offset from the main wall allowing the exposed brick to be part of the room behind. You were going to build a wall anyway so here a little bit of thought yields an expensive looking fireplace doubling up with a characterful wall on the other side.

Perfect fireplace for a wood burner.

A few dimensional suggestions: The front buttresses are 225mm or one brick wide and thus the wood sections are 225mm square. The width between buttresses of 1.6m gives room for logs to be stacked by the stove and the 1.5m height between the floor and the main cross beam works well.

fun with the band saw

The Zampi (Italian: paws) profiles go like this:

Draw a centre line, mark the radius from the corner, draw a 30 degree angle from the corner, the big curve follows from the centre line intersection.

Double click for a closer look.

 

 

You might be going to use a flexible flue and this will need supporting above the stove. A steel ladder frame that can be slid forward and back a bit will make lining up the stack and the stove really easy. Between this and the stove fit a removable flue section to make cleaning easy.

A big stove like the 14kW Clearview shown here is best connected to water or it will make the room far too hot. To get a simple gravity feed put your tank on the other side of the wall and inside an airing cupboard. That’s another lot of plastering avoided and the core of your heating system done. BTW – I’m happy to advise on tanks and stoves and to supply them too. There’s a contact form below.

P.S. Here is a 2m wide version drawn with the non plastered wall theme – i.e.with low cupboards that can incorporate the DIY fan-coil heater.

Inglenook fireplace

Like what you’ve read? Find more essential reading on my e-book

‘Dream House – Down To The Details’ 101 things you should have thought of.

Heating for your eco-house

For more straight thinking, this time on heating, have a look at the ultimate Eco heating system which integrates heat pumps stoves and solar.

You really should get this right and there are many wrong turns where multiple energy sources are integrated.

More on this topic in LIST OF POSTS

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Heating News – Autumn 2017

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Off grid for under £2,000 – Case study

Fridge, lights, TV, computers? YES.   Kettle, toaster, hairdryer, washing machine, dishwasher NO. These were the parameters for a minimalist off grid PV system for a friend’s pod. Low power but low price. Tempted by an ad for some second hand panels from Canada we were soon knocking on the door of Bimble Solar near Brighton. We fancied 4 PV panels and were shown into a large barn with stacks of panels up against the walls. ‘Which ones are ours then?’ we asked. ‘Any ones you like’ was the answer. They were mostly second hand and we settled on the 300Watt ones from France; defunct solar farm casualties. Apparently there are many solar farms either going bust or upgrading so there will be heaps more cheap panels to come. As panels should last 20 years it makes sense to start off with cheap used ones – who knows what the possible upgrade will be in ten years or so.

20 minutes and £1,740 later we had the kit in the car with batteries to be delivered later. Here’s the kit list:-

4 x 300W PV panels, 4 years old  and £99 each.

So this is the 1.2kWp array

40A 12v/24v MPPT charge Controller – New Model Tracer4215BN

This charges the batteries efficiently and safely.

Optional MT50 MPPT Display meter for New Tracer BN Charge Controllers 10a 20a 30a 40a

Tells you what is going on with every part of the installation.

Victron Phoenix 1200W, 24V inverter

Much favoured by the boating community this turns 24V DC into 240V AC, up to 1.2kW. The output is pure sine wave AC so good for computers and TV.

Sterling 200Ah Sealed Battery 12v

Two of these in series gives 24V. Big and very heavy there is no doubting the quality and 200Amp.hours is at the top end end of the range.

All the connectors and wires were included and the wiring turned out to be very simple.

To keep the wiring neat and safe I like to use two consumer units; one for the low voltage DC side and another for the 240V mains side. The bus bars and the DIN rail in the consumer unit make wiring quick and convenient and when all the units are board mounted, with wires going behind the board, it all looks neat and tidy.

PV Off-grid wiring

Once the fridge was turned on the display showed a draw of just under 5 amps for a few minutes at a time. This was not going to tax the 200Ah batteries at all. Every bulb in the place is an LED so no problems there and there will be enough left over for TV and computer and to fire up a gas water heater.

The proposed Rinnai 16i in-line gas water heater draws 68W, when running, which is easily manageable for short periods. This LPG heater will provide instant showers and hot water with twice the power of many combi boilers. If fed by pre-warmed water the unit dials down the gas consumption to produce the same output temperature. This enables any solar heated water to cut down gas use – a project for the future.

The supply of power is looking very generous for the summer but will hopefully still be close to requirements in the dark winter when the input from the panels will just about halve.

Even this starter kit gives a feeling of independence and empowerment and, of course, freedom from price rises for years to come. To run washing machines etc you’d need a 3kW kit which comes to about £5,000. A full 6kW mains equivalent kit would be nearer to £10,000.

There is a section in my book ‘Dream House – Down to the details’ on Amazon – here – which discusses the idea of using systems like these as large uninterruptible power supplies, in daily use but keeping the mains as more of a back up. There are charge controllers (e.g. Victron) designed to do just this so the UPS concept is really quite simple to implement.

£1,000 heat pumps

The Bimble web site is a delight to browse through. I was particularly taken with the circa £1,000 heat pumps at a fifth of the usual prices and looking good value with Toshiba compressors and modern r410a fluid. A heat pump is just like a large fridge, and usually just as reliable, so one of these might be worth a punt at this price but you might need advice on what to connect them to.

In all probability these are Chinese but they often come with quality European components so they should be mechanically sound.

Have a look here at a system especially suited to integrating heat pumps.

FYI the UK Renewable Heat Incentive pays 7.63p/kW.hr on air source heat pumps.

Solar Immersion Controller SOLiC 200 – free(ish) hot water from your excess solar

Another find on the Bimble site.  If you don’t get much for exporting your PV power to the grid this little box can divert it to your immersion heater. The original kit that could do this disappeared off the market so it looks as though the SOLiC 200 has stepped in to fill the gap. The £200 price will be repaid pretty quickly if you pay a high price for electricity, however if you are defraying gas use in the UK then maybe not. Gas is still really cheap.

 

The Rinnai 16i in-line gas water heater – a solution for guest houses?

This useful boiler heats water just as you use it but without the losses incurred from storing the hot water in a tank. The water is delivered at the set temperature which can be quite low compared to stored water. It is powerful too – like having a couple of combi boilers together. Being much simpler than a combi though, the Rinnai only costs £500 and for larger properties it makes sense have more than one with the added reliability when the outputs are cross linked.

The Rinnai is marketed as a base for a tankless system but its modulating feature makes it even more effective when used in conjunction with a tank. For example if you were running a small guesthouse, needing an unlimited hot water supply, you could use wood and solar to heat the tank and only use the Rinnai to top up the hot water coming from the tank when necessary. The boiler only uses enough gas to raise the water temperature to the set point so when pre-warmed water arrives the gas throttles back. With cheap energy sources pre-heating  the water, gas consumption will plummet but constant supply will be maintained automatically. The Xcel heat banks I supply have been used like this for years so if you want to discuss such a system let me know.

Free air conditioning?

If you were in Italy this summer you might have experienced temperatures of well over 40 degrees. As there is almost a whole year to go before that all starts again perhaps a cool look at some air conditioning might be in order. You’ll know those portable units where water is evaporated and exhausted to the outside through a tube. It takes a lot of heat to evaporate that water. Imagine trying to boil a large saucepan of water dry on your stove – that’s how much heat is needed and how much heat would be removed from the air. So if a lot of water can be evaporated then things will tend to cool down, a lot. The cheapest way to employ this principle is to mop your floors in the early morning and open up the doors and windows to let the moist air out before you have to close up again. Chilly floors will get you comfortably through the rest of the day.

My school in Kenya had a cool room made with wetted charcoal walls; a great example of the power of water evaporation. If you fancy making an evaporative aircon unit I have a design using charcoal, irrigation hose and corrugated pipe …. happy to share.

Nights can be unpleasantly hot though so what about them? Well the outside temperature falls off a good 10 degrees from the highs of the day and if it wasn’t for intruders and mosquitos it would be great to open up the windows again, especially the downstairs ones where natural convection will move the hot air up through the house. Mosquito nets over barred windows make a good start but it takes a lot of air to make much difference so a fan on the window sill will help to pull in that lovely cool air. The air it displaces will need to get out so other netted windows will be needed upstairs.

Liquid pool cover – HeatSavr Ecosavr Fish

Evaporation is the last thing you want on your pool, it not only lowers the temperature, it uses significant amounts of precious water too. A liquid pool cover is the answer. One or two £20 fish shaped sachets of liquid in your strainer slowly dose the pool with a molecularly thin coating that floats on the top and prevents evaporation for 5-6 weeks. Well done Martin Daykin for trialing this product and telling us about it. It works.

Heat bank tweaks

The heat bank specification just got better. No doubt you know this is a stainless steel tank with a complete plumbing solution – pumps, valves, wires, solar coil etc – all fitted to it and ready for a speedy installation. Two new mods are available. To prevent the heating pumps depleting the hot water too much there is a new cut off thermostat; unless extra heat is being supplied to the tank the pumps will cut off to leave a block of hot water at the top of the tank.

Home automation enthusiasts will welcome a couple of extra sensor pockets for temperature monitoring. One use might be to turn on the domestic hot water pump to deliberatly destratify the tank, when it becomes very hot, before the overheat stat turns on the heating. Now the hottest water is sent down to the cooler bottom of the tank and as the whole tank becomes uniformly hot the effective capacity is increased.

There is still time to get your heating organised before winter so do get in touch if you want to discuss your strategy.

 

 

Heating News – Spring 2017

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Grid parity – are we there yet?

Photvoltaic panels might not be particularly efficient but they are certainly simple and cheap to run. Stick ‘em in the sun and they make electricity with no further ado. This is why over the next five years large scale PV solar for the grid will be level pegging with the existing power generation costs. So this is grid parity. As power costs rise and panels get cheaper and better, the post parity world should see PV power starting to put the brakes on energy price rises. Of course PV power won’t dominate, there just won’t be enough of it to do so, but the underlying principle will be self evident and compulsive enough to set the stalled PV train in motion again.

There is another reason to give PV renewables a boost. The nascent electric car era is going to tax the grid beyond current capacity. While petrol stations stand empty the grid will be flat out, trying to keep up. A world where the car in your garage costs virtually nothing to run is getting tantalisingly close but the Government clearly needs to act now and raise incentives for domestic PV installations.

Right now though, on the domestic front, parity is more complicated despite panel prices having fallen to around £1,000 per kWp plus the installers cost.

Take a typical 3 bed UK house with annual electricity bills of £450. A 4kWp array costing £6,500 will make a derisory £320 a year in savings and FIT income. Payback over 20 years just says ‘no way thanks,’ so no immediate evidence of parity being anywhere near.  However, before we give up, lets take another approach and scale up enough to run a small heat pump; enough to knock out half (no sun at night) the £650 annual gas bills and make the other half at about the same cost as gas would have been. A 6kWp array making around £450 a year and costing £8,500 to install plus another £5,000 for the heat pump makes a total cost of £13,500 for an effective return of £875.

That 6.5% return looks a bit more interesting! What if we took advantage of these crazy low borrowing rates and borrowed the £13,500 from, say, Sainsburys for an annual payment of  £2,267over 7 years? We can expect a little help from the Renewable Heat Incentive payments for 7 years applied to the air source heat pump – like £770 a year according to the Ofgen example.

Deducting the £875 savings and the RHI £770 you effectively pay £622 for seven years until the loan is all paid off. You are then left with £875 a year in benefits (and rising) for as long as the kit lasts, which should be a good 13 years. This looks like a sensible way to prepare for a comfortable retirement; almost like a pension. Put an electric car in the garage and another major cost will be eliminated.

Very attractive RHI incentives are also available for solar thermal panels (although making DHW only). £220 a year in the Ofgen example. Even more noteworthy is the emphasis on the more expensive ground source heat pumps where the example returns jump up to £2,100 a year for 7 years. They not only pay a much higher tariff (19.64p/kW vs. 7.63) but the higher COP of the GSHP affects the calculations in your favour. The calculations are based on your energy demand taken from your EPC certificate and you can easily do them yourself.

My definition of grid parity is when it pays to borrow money to buy solar PV. On that basis I’d say we are still some way off but the RHI incentives are making combined systems worth considering.

You can see these and other ideas explored more on an eco-house design here. This house is designed to be virtually off grid and able to provide a separate living unit for grannies or Airbnb paying guests.

To delve deeper into eco-energy concepts you might like to look on Amazon where you can download, for Kindle, my book ‘Dream House – Down to the details’ £2.45. Details

 

For the Italian readers – low borrowing rates – time for a heating makeover.

There is no getting away from the fact that the cost of heating in Italy is a major issue. The wood/solar solution is usually the answer but the high installation cost often leaves householders trapped in an expensive rut. OK, so lets go back to Sainsburys to borrow £8,500 for a perfect solar/wood stove/heatbank solution to be delivered to your door. £152 a month (£1,824 a year) for 5 years gives you a delightful system that will run for around €1,200 a year. This is deluxe kit. The best stove, the best heat bank and a huge 3 panel solar array.  You’ll be warm as toast and there will be masses of hot water. The heating even works in a power cut so you will be safe and even able to cook if disaster strikes. Sorry to keep flipping currencies, but this means that if your heating bills exceed £3,000 a year then it’s time to have a think about a makeover. So many owners of Italian houses spend double this but there is no need to be one of them. If you need a hand to figure out if a makeover would work for you, just get in touch on the contact form below.

A plug for Italian eco-heating.

Heating in Italy

Word is getting round about eco-heating in Italy. See The Daily Telegraph article here.

In praise of the Casio solar watch.

This story started at the clock museum in Greenwich. I was admiring John Harrison’s (he of the Longitude prize) sea going clock, with all the elaborate pendulums and springs, and realised that his strange machine was more accurate, even at sea, than my £1,000 Breitling Aerospace titanium watch. Now I loved that watch but this was too much to bear so it was sold straight away to someone in the office and five of us there did a deal to get some Casio Waveceptor Toughsolar watches at £130 each.

These watches tune in to the atomic clock at Rugby each night so they are absolutely accurate. The expression ‘What do you make the time?’ is redundant, the time is what it is, period. The first pip goes exactly when the second hand hits the top, even when the clocks change twice a year the hands wind an hour on or off during the night. There is no knob on the right to adjust the time (obviously) and this facilitates the sport of asking owners of expensive watches why they have a knob on their watches. ‘To adjust the time – really?’

The face of the watch hides a solar panel and the metal strap lasts without wear so there are no tedious battery and strap replacements (£30 and £70 respectively on the Breitling).

All this was 10 years ago and the watch, being waterproof, has almost never been off my wrist. It just ticks away faithfully and relentlessly, over 315 million ticks so far, a number of tiny mechanical jolts that beggars belief.

So after the first ten year stint old watch, I salute you.

Small, affordable eco-house

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State of the art eco-house is easy and cheap to build.

Check Google images for tiny house, small house, eco-house, green living module or just a modern house. See anything you could imagine building reasonably cheaply and easily then enjoy living in?

Here is something to stir the imagination, a concept sketch of the Original-Twist Eco-house. And this is not just an eco-house by name; it is a thoroughly engineered, practically off grid living module where the technology comes first and the house is made to fit it.

On the first floor a massive structurally open space gives adaptable options.  There is space to the left for a huge kitchen diner (7m x 3.5m) or a smaller kitchen and a bedroom/study. Next comes the massive living room (5m x 5m). The raised bedroom platform (4m x 5m) follows and off that a bathroom and an office or child’s bedroom. These are exceptionally large and impressive spaces and with some expensively extravagant oak frames supporting the roof they are characterful too. Everyone loves heavy rustic looking beams and that ‘barn conversion’ look.

Bye the way; as a protest against flimsy curtain rails there would be heavily mounted industrial Henderson tracks. Even Tarzan could be trusted to draw the heavy curtains across the windows or the bedroom section.

First floor layout

On the ground floor a properly large garage at one end and a full height kitchen conservatory at the other, contain a variable layout of rooms to make a separate living unit. Thus the upper and lower floors combine to make a family house or each make fully independent living spaces. There would be no difficulty making a Granny annex or securing some rental income to pay back some expenses. The foundations for the conservatory should be laid from the start to make it easy to add that on later.

Care has been taken to keep the house very basic and thus avoid unnecessary overspends. We want wonderful living spaces and enough cash left over for something special in the double garage. The simple construction suits ICFs (giant foam Leggo blocks with concrete poured in). It makes more sense to stick to ICFs all through; one contractor, less interference and anyway the clever flooring solution that comes with Quadlock ICFs is worth having. The extra thermal mass is a big plus point and also gives good soundproofing between floors. ICFs are particularly suitable for the wooden cladding shown here although the choices are almost endless.

Another cash preserving strategy will be to delay a whole list of things until after moving in.  The sooner you move in the sooner you stop paying rent somewhere else? The ground floor kitchen/conservatory, home cinema, and all the solar panels can all wait until later and the rent you save will help pay for them. Self builders will appreciate the idea of finishing one floor and living-in to finish the other.

A house designed for the hard times of ex-growth Britain deserves a catchy name – we’ll call it The Brexit.
The side and rear overhangs allow the house to fit into a small plot. It can be built to within a whisker of the boundary and yet you can still walk round the outside. The balcony at the front echoes the overhang to give a pleasing uniformity.

The Brexit is quite small which leaves something in the budget for all the latest mod cons like the home cinema, that car in the integrated garage and of course the eco-kit  and the heat pump pod in the garden. It may look fairly conventional (planners note) but the eco-credentials of this house are exemplary.

The south side has plenty of glass which adds to the feeling of space and allows for enough solar gain to take us into passivehause territory.

Of course the eco-technomologicalness will be state of the art, not just token gestures as in many eco-houses but the highest expression of the art. The 24 Sunerg hybrid solar panels actually dictate the size and shape of the roof and the roof trim panels are fixed directly to the panels (PV and wet solar are both 2m x 1m).  4 of the panels on the steep roof will be wet to give a massive 8sqm to feed the Original Twist twin tank heat bank design. If you are involved in creating anything remotely like an eco-house you should study this system here. The other 20 panels give a nominal 6kWp and a real 2-3kW in the winter to run the little air source heat pump which also does some neat heat recovery from the house and uses some ground heated air too.  Batteries make a huge UPS which largely makes the mains supply more like a backup especially if combined with the batteries in the electric car. The Brexit is designed to be future proof as much as possible. More detail can be found in the e-book ‘Dream House – Down to the Details’ here. Don’t start any project without investing £2.45 on this book.

To convert the living space into a dining room the table comes up from the floor – (see the design here)…… the TV disappears behind a roller cover and the sofa glides back into the recess behind it; fanciful maybe but it makes excellent use of the space and easily accommodates large dinner parties. The sofa mechanism is quite simple with the sofa parking on top of the cover door when it is deployed. The table concept is equally simple but pretty spectacular in action and the small extra cost effectively produces an extra room.
With all the clutter cleared away there is plenty of room for partying with the ‘bar height’ raised platform making a safe place to put food and drinks. This house really is an entertaining machine.

And what a super house to start the day in.  A cuppa in bed on your lofty bedroom, as the heavy curtains automatically retract you watch the morning news on the big screen; time for showers then a sunny breakfast downstairs before nipping through to your dream car. The garage doors rise automatically and you are off on your day.

How much roughly? 188 square metres at £800 is around £150,000. £25,000 for the eco-tech and heating systems, so maybe £180,000. Call it £200,000 plus the plot cost. Looks like a lot of good living for the money, and don’t forget, this versatile house has considerable earning power and almost no running costs. Think clever, think Brexit.

More on this topic in LIST OF POSTS

Dream House – Down to the details

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dream-house-down-to-the-details

 

Dream House – Down to the details

An e-book on building or enhancing your dream home, covering over 100 topics including low energy heating trends with implications for the eco-homes of the future.

My new ebook is available for Kindle, Fire and can also be accessed with the Kindle app for your phone or PC.

Your dream house – you know you have to get everything right first time but there will inevitably be some omissions which will haunt you later and almost certainly incur unwanted costs. This book tells you how to plan and execute without stress, managing time and cash flow just like a professional. Although occasionally technical, the book makes light, conversational reading and guides you through topics such as eco-heating strategy, catering for entertainment, security and communications, how to make a fabulous kitchen without spending a fortune and dozens of smaller, but important, topics which will enhance your final house design to the perfect state you’d like. If your objectives are for sustainable living you will be rewarded by a wealth of stimulating content.

This book will pay for itself many times over.

Available now on Amazon for £2.45

Paperwhite Kindle readers will appreciate having the pictures reproduced in colour so here is a

selection below. Double click a picture to enlarge.

Sun tracker garage

Sun tracker garage

Heat pump power

Heat pump power

knife-rackflush-sinkclearview-in-siepi

Ultimate Eco-heating system

Ultimate Eco-heating system

 

 

 

 

stacks-of-power-graph

 

 

 

 

bangs-for-your-bucks-uk

heat-bank-siepi

aermec-fan-coilsflower-bed-in-pavingenergy-use-chartbath-tapswood-stove-heat-dump

Heating News – Jan 2017

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Heating News 2017

2016 has been pretty uneventful on the heating front. Home automation is probably the main game changer and, if you really want to, you can now literally shout at your heating from near or far.  In fact you can shout at many inanimate objects from now on, not just computers which many of us have been shouting at for years.

Prices for heat banks and stoves remain unchanged and transport to Europe still runs monthly. No Brexit issues here, so do get in touch if you need any help.

Eco heating system

Ultimate Eco-heating system

Ultimate Eco-heating system

My ultimate twin tank system has been designed and launched and it can be viewed in detail on this site.  While a single heat bank provides an excellent way to integrate just about any heat sources you care to throw at it, there was scope for improvement when it came to dealing with heat pumps.  The twin tank solution not only addresses all their shortcomings – high flow and lower temperatures – but most of the other heat sources are enhanced in the way they operate.  In particular the solar stripper circuit kicks panel performance up significantly, allowing much bigger arrays to run all year round.  For anyone in need of the ultimate high powered eco-heating system this is it.

Dream House  Down to the details

Just launched on Kindle for £2.45 this is essential reading for anyone improving, building or restoring a house. Actually it makes an entertaining read for anyone who just needs a stir to the imagination. There are well over 100 tips, tricks and tweaks to enjoy but also to serve as a checklist for some of the less obvious tasks on plumbing, wiring and, of course, heating strategy and the changing face of energy management.  Many suggestions could save significant amounts of your hard earned cash as it costs much more to fix things after the main jobs are done and all the workforce has moved on.  So don’t miss out, get it downloaded and start reading.  There are lots of colour pictures and diagrams so it reads best of all on the Kindle app on a PC, a Kindle Fire, even a phone.

PV electric car charger garage

Sun tracker garage

Sun tracker garage

You can find a full description and picture of this here https://originaltwist.com/2016/02/29/electric-and-hydrogen-car-charger/   Think of a garage shaped like a huge fat slice of Edam cheese where the red bits become PV panels and you have the idea.  PV panels like to track the sun so the whole thing is on a turntable to improve performance by over 20%.  The garage can fit into a tight space because it will turn your car all the way round with no reversing needed.  O.K. I know it seems a bit far fetched but I see no technical impediments and if it has an Airbnb pod on top earning £80 a night you might grow to love it.  Any machine that gets paid to fuel up a virtually maintenance free car and earns some £12,000 on top has to be lovable; doesn’t it?

Cheap LED bulbs

I took my own advice and continued to buy LED bulbs from http://www.trillion.co.uk on a deliberate replacement program without particularly waiting for old bulb failures. Now the house is almost entirely LED lit so I will start to compare monthly bills as the year goes on.  I continue to be impressed with the quality and price of these bulbs and I love the abrupt halt to the tedious bulb replacement jobs of the past.  How about you?

Automated electric kettle

The £4 time switch from Amazon, on the plug of a standard electric kettle, has worked fine for a year. As long as the kettle is filled and the switch set to auto, the kettle clicks into life in the early morning and at tea time. It’s a small idea but I just love it, especially on cold Winter mornings when an extra few minutes in bed are so welcome.

Hot water for campers

A friend has a remote shed in the country and wanted a cheap hot water system for washing up and showering; something better than the cold water hose on site.

The final solution has come off the back of the envelope and is up and running.

It has 3 basic components.

1/. A feed and expansion tank with a ball cock (actually a lavatory cistern) is hauled up into a tree to give good water pressure and provide an open vented feed to the tank below.

2/.A steel drum standing on end over a brick fire box with a crude chimney at the back. Cold water is fed to the bottom of the drum via a pipe (from a defunct drum pump) fitted via the large port on the top. Hot water is drawn off the smaller 1” port at the top of the tank.

3/. The feed from the drum could be boiling hot so a temperature limiting valve blends in cold water to make it all safe. It is neatly screwed directly onto the 1” port on the drum and the blended water then connects to a hose pipe which supplies a tap and a shower in the woods.

So there we are; a cheap but very workable solution for shed owners looking for home comforts.

N.B. If you are making the firebox make a ledge some way up for a grill tray. Then you can have a barbie and have hot water to wash up with later.

Solar panels for Italians

I like to thank my clients in Italy with a pretty amazing deal on a big solar panel kit. 3 panels, a pump-station with controller and all the fluids for just €2,000 + IVA.  Every incentive to become a client in 2017 and get your heating issues sorted.  English clients can also benefit although transport costs make it less attractive.

Zero gas – nearly

You may have heard it all before – heat banks, solar and stoves – and wondered if it all really works.  Well, to reinforce the point let me say that as our LPG gas tank was lasting 7 years between refills we had it removed and now use small gas bottles. Used mainly for cooking and just occasional gas boiler use the bottles last for months rather than weeks and it is easy enough to swap them over at the ferramenta 3 or 4 times a year.  This would only be possible with a properly engineered wood and solar system.  If you spend over €1,200 for a year’s hot water and heating in your Italian house it might be time for a strategic review.

Wishing you all a very happy and warm 2017

Patrick Littlehales

Eco-heating system for heat pumps

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Ultimate Eco-heating system

Ultimate Eco-heating system

Ecological heating (Eco-heating)

NOTE: Dec 2019 This design will still suit many configurations but much cheaper PV panels have changed the rules somewhat. Suggestions for an update, and a simpler diagram, are here at the 2020 revision

Also the RHI incentives have all changed so by all means have a look below but the 2020 revision is more up to date.

The Eco-heating goal is simple.  To use free or green energy (solar/wood) so effectively that expensive fossil fuels, energy bills and the carbon footprint disappear.  The only reason to be attached to the grid is to supply it; well not quite, we might need the grid to smooth any fluctuations but we certainly don’t need much of it or, even better, none of it.

Modern houses are well insulated and need a lot less energy to run than before and a few technological advances have made Eco-heating absolutely viable. PV panels are more powerful – only 3 needed to make 1kWp now.

As a starting point, a tank of water – a heat store – is required to integrate various heat sources and demands. A single heat store makes an excellent heating system but two tanks are altogether much better, especially when it comes to integrating solar and a heat pump. So much more is easily optimised with twin tanks that this is the future for eco- heating systems.

Before you start to plan your own ultimate heating system there are a few points to consider:-

Photovoltaic panels (PV) rarely produce their rated output.

On a bad day they produce only around a third of their rated output – say 100W per panel.

Background electrical demand (fridge, computers, lights, TV etc.) can often be as high as 1kW

The PV panel array will have to be much bigger than the usual 4kWp (12 panels) for there to be enough surplus power to make an eco-house.

 A heat pump takes electrical power and delivers around 3 times as much more energy in the form of hot water. This engineering miracle might be the core of the system, but …

The power multiplier

The power multiplier

…. the times 3 trick (coefficient of performance or COP) is highly variable, and depending on outside temperatures and delivery temperatures, can vary from 2 to 5. The manufacturer’s quoted COP is for very specific conditions which you might not see very often.  Even the quoted power output of a heat pump will not be reached when it is very cold outside.

 

Air source heat pumps are a better choice than ground source heat pumps

They cost less and are easier to install. For the full argument see:-

https://originaltwist.com/2015/02/27/air-source-heat-pumps-and-the-renewable-heat-incentive/

https://originaltwist.com/2014/03/19/heat-pumps-in-southern-europe-air-or-ground/

Unfortunately the RHI payments are biased heavily towards ground source which will skew the decision. Even the government is confused about efficiency and we can punish their oversight with the Original Twist Hybrid Heat Pump … four tanks now – how exciting.

PV + heat pump = Free heating

A heat pump on a COP of 3 redresses the shortcomings of the PV panels on that bad day, so a PV and heat pump combination can deliver 300W for each panel and two or three times as much on good days.  This energy, in the form of hot water, can be delivered to underfloor heating which usually uses about 50W per square metre of floor and never more than 100W (which would make your feet hot).  So, for a rule of thumb, 8 PV panels will do 50 square metres of heated floor area. Then add up to another 10 panels to cover background consumption.

Two things to take on board at this point.

1/.If you are going off-grid your energy storage (in batteries and the water tanks) will tide you over for the bad days and the wood burning stove will always cover all the heating and domestic hot water demands.

2/. A popular size (and so a cheaper size) of PV rig is based around 6kW and this implies a matching 18 panels. Have a look at the overclock and tilt theme here to see why you’ll increase that to 24 panels.

Therefore, most self-supporting Eco-houses are likely to have 20 – 24 PV panels on the roof; a lot. The calculation for a Passivhaus is scaled back considerably; there might be no floor heating at all and just fan-coil units , even so there will still be a lot of panels to cope with the bad days.

Air source heat pumps run much more efficiently during the day when the air is warmer.

Not only more efficiently but combined with PV panels much of the daytime energy produced is free.  Obviously big PV and a slightly oversized heat pump can produce excess energy which could keep the heating on after the sun goes down. The surplus energy will need to be stored in tanks of water – big ones.

A house with high thermal mass will also work better in this respect.

Solar thermal panels are much cheaper and much more efficient than PV. and, given some sun, they do produce very hot and free high grade water heating. Cheaper P.V. panels are challenging this space but this system leaves both doors open. Massive solar is hard to manage and here again big tanks are part of the answer.

Solar thermal panels can be made to run more efficiently.

Solar panels can only heat a tank that is cooler than they are. In winter when the tank is usually already hot and solar is weak the panels often stop working altogether.  Given 2 tanks however – one hot and one cool – the panels will run almost daily throughout the year and this dramatically improves effective panel efficiency. The Original Twist solar stripper circuit decides which tank, or both together, can use the available heat more favourably.

A pair of 500 litre tanks are only 2m high and together under 1.5m wide.  Tanks up to 500 litres can be made of light gauge steel so they are relatively cheap and easy to handle. However there is a case for making the cooler tank 1,000 litres – it’s a cheaper energy store than batteries.

Gas boilers – not quite redundant for big houses

On the coldest night the heat pump with reduced power output and the lowest COP might be struggling, especially if it was sized within the limitations of single phase electricity. A gas boiler is a towering powerhouse by comparison, producing instant high grade heat at a low(ish) price. Hot water recovery times are just minutes and a shower could run hot forever if required.  For a larger eco-house, a gas boiler for very occasional use makes sense and ensures that there are no compromises to comfort whatsoever.

Under floor heating is not always best.

Bedrooms need to be heated quickly, usually briefly, and preferably not with a hot floor under the bed.  Floors of upstairs bedrooms are often reasonably warm already because they are above rooms which are heated all day so paying to heat them more makes little sense.  The answer for bedrooms is the fan-coil unit which is essentially a hot water powered fan heater. Not only will they heat the room in minutes, but connected to a suitable heat pump they will cool it as well.  Air quality can be enhanced by UV purification, a boon to asthma and hay fever sufferers.

Towel rails are different.

After your shower the towel rails will need to be on long after you have got up or gone to bed. The timing and heating requirements for towel rails is completely at odds with the rest of the system and they need to be properly integrated with a dedicated pump and timer.

Wood burning stove

Mankind has been sitting round fires for thousands of years; for many people it is unthinkable not to have a real fire in the home.  We are talking eco-heating here so an open fire is out of the question but a good stove is much nicer to live with anyway.  A big stove with a big view of the flames will be too hot for most rooms so it will need to be connected to the water tanks in order to take some heat away. That’s no bad thing as high grade hot water is not so readily produced by the heat pump. A well matched stove can usually cope with all the hot water and heating needs which relegates the heat pump to an auxiliary role and certainly means that smaller heat pumps can be used.

Controls

Although it is not an absolute requirement, the eco-heating system will work much better with a home automation system such as the Z-Wave Vera. The hot water circulation system, for example, can be activated by sensors in the bathrooms when they turn on the lights. Temperature sensors and relays to activate pumps and valves can be found in the Qubino Z-Wave flush relay which has a built in temperature sensor.  The destratification routine (see below) can be triggered by the integrated temperature sensor and the short pump runs monitored by a controller which easily copes with ‘if this then that’ situations.

Efficiency – the humbug

Just a reminder; the sun is free. There is no need to agonise over panel efficiency. Flat plate thermal panels are cheap and reliable so if you need more power just add more. Anyway, during the hotter months they are more efficient than evacuated tube types.

To store daytime heat pump production, the target temperature needs to be raised and that is less efficient than driving the under-floor heating directly. Again the pump is usually running free, courtesy of the sun, so the efficiency doesn’t matter.

Aircon and the renewable heat incentive

The RHI only applies to heating only heat pumps. If you want aircon you should add a separate chiller unit. The diagram above will only be a little different.

 

The Eco-heating system

Considering all of the above your ultimate Eco-heating system should be like this:-

Much of the suitable roof surfaces will be covered in PV and thermal solar panels.

An air source heat pump

Air conditioning via heat pump

Under floor heating on the ground level

Fan-coils in bedrooms

Fan-coils in some living rooms for air conditioning

A gas boiler (optional)

A twin tank heat store system. 1000 litres + 500 litres.

A wood burning stove connected to the tanks

A system that can optimally integrate all of the above with no compromises at all is a tall order.  Here it is though; the Original Twist Eco-heating System.

Two tanks it is then – one hot one cooler – but with some sound thinking around the connections to the heat sources:-

Domestic hot water delivery.       

Fresh and pressurised water is heated by the hot tank via a plate heat exchanger – standard heat store practice. However, as the hot tank water will be rather modestly heated by the heat pump, the ability of the plate heat exchanger to cope with icy fresh water can be compromised. So to warm the incoming water it first runs through an internal coil in the cooler tank before getting to the external heat exchanger on the hot tank. The pre-warming is not mission critical so there are no controls or pumps to worry about. It’s just a passive coil in the cooler tank.

Back on the hot tank the usual temperature limiting valve – anti scalding – has been dropped in favour of electronic regulation of the heat exchanger flow pump with a Steca  TF A603 MC+ controller. This modulates the pump to give a precise output temperature and so leaves more water at the top of the tank ready for more showers. The flow out of the heat exchanger and to the bottom of the tank is also cooler which aids cooling of the solar coil.

Water circulation around the house is essential to save water wastage and eliminate that annoying wait for hot water.  The same Steca controller also regulates the circulation pump speed.

Preheating the domestic hot water via the cool tank not only makes a heat pump a feasible hot water maker but it also raises the efficiency in a subtle way. The water in the cool tank is heated just enough to supply the floors and fan-coil units and a heat pump does that very efficiently. Blending this cheaper energy into the hot tank system gives an efficiency boost and also allows the hot tank to be maintained a little cooler which gives another efficiency boost.

Other potential heat inputs to the hot tank (wood, solar and gas) are not disruptive to stratification so hot water drawn from the top is always ready for service.

The solar stripper circuit.

Solar thermal panels connected to a hot tank which is already hot – as it would be with a stove or heat pump keeping it ready for hot water delivery – will be effectively switched off in weak sunlight.  But given access to a cool tank they will leap into action at the first glimmer of sunshine, practically every day of the year. Low temperature solar flow addresses the coil in the cool tank first but as soon as it is hot enough it is switched to the hot tank. The flow emerging from the hot tank is usually still very hot so the return flow to the panels goes back via the coil in the cool tank to strip out some more energy.  The panels not only run throughout the year but more efficiently due to a cooler return feed.

The Original Twist Solar Stripper Circuit achieves all this with a special 3 port Coster valve that does not interrupt flow as it changes over. The solar pump is started by the cold tank sensor and everything is managed by the Steca TR 603 solar controller which also modulates the pump speed to keep flow temperatures up.

With two solar coils in use, a bigger solar array can be used without resorting to the absurd remedy of using an external plate heat exchanger and circulation pump. Absurd? Imagine sunrise, the panels and the pump start up, the tank is destratified and your morning shower is there no longer. Dooh!

Heat management

With high grade heat sources connected – wood burning stove and solar – the hot tank can get very hot. High grade heat is valuable so the system hangs on to it as long as possible but excess energy will have to be moved eventually. The system does this in 4 stages, each triggered by a cascade of temperature levels.

Destratification  – First the pump for the hot water plate heat exchanger is activated for short bursts. This moves hot water down the tank and effectively increases its capacity.  The process is limited to the maximum return temperature a wood burning stove can tolerate before the back boiler starts to kettle.

Blending the tanks – If surplus energy is still arriving, a valve connecting the hot and cool tanks opens and the cool tank starts to warm up via a thermosiphon. In this way a wood burning stove would provide for masses of hot water first and then go on to address the central heating. The valve sets to open in a power cut and is controlled by the overheat stat on the hot tank.

Overheat thermostat 2 – In the unlikely event of the cool tank reaching 70 degrees, the overheat thermostat starts the heating pump to dump heat to the heating system or a purpose heat-dump fan-coil.

Power free heat dump – As a last resort, and in the case of a power cut, a power free valve in the hot tank is activated to flow cold mains water through a small coil and send energy down the drain.  It is hard to envisage a system where this would really be required but the option is there.

Heat pump integration

The floors pump and the fan-coils pump first draw water from the tank, the repository for free energy. The heat pump starts when the tank temperature becomes too low and then the flow goes directly to the floors or fan-coils. The latter can only be achieved if the heat pump circulation pump flows slightly more than the demand pumps and there are a couple of ways to ensure that. When the heat pump is running under PV energy during the day it will top up the tanks or supply heating depending on demand. Heat pump set points to suit fan-coils or floors will be triggered by the relevant circulation pumps and by the PV output.

Controls

You might imagine that a sophisticated control system would be needed but that is far from the case as many of the functions are independent of each other with only temperature levels causing any interaction.  For example, the circulation pumps for floors and fan-coils are only activated by programmable thermostats which do not control the heating.  The heat pump is timed and only tops up the tanks if temperatures fall enough to call it, otherwise the wood and solar do the job. Destratification and blending are all independently triggered by temperature levels.

Simplicity is a major benefit. Should any problems arise there is no need to call in a specialist expert.

Who makes it?

In the first instance I will help you to specify and match the various elements of the system so that a bespoke specification is readied for production by the British manufacturer.

The system is based on a standard heat store with a few additions and those additions contain nothing new or untested.

Despite the simplicity this is the absolute cutting edge of Eco-heating systems.

Pre-wired and plumbed this is a quick and cost effective way to solve all your heating issues. The successful integration of wood and solar means a smaller and less expensive heat pump can be used with fewer P.V. panels to drive it. Considering all these savings and minimal running costs the Original Twist Eco-heating System is what every new Eco-house needs.

To see if this, or a single heat store, would be suitable for you just use the contact form and we can discuss your requirements.

 

The Original Twist Eco-heating system

Features summary

Stainless steel tanks – should last a lifetime

Total of 1,000 – 1,500 litres for energy storage

One cool tank for virtual stratification.

Mains water pressure is maintained but tanks are unpressurised

No hot water is stored – legionnaire’s avoidance

2 stage hot water heating for heat pump compatibility

130Kw heat exchanger for hot water making – more if required

Hot water circulation

Anti scalding

Suitable for solar input of up to 14kW

Solar stripper circuit for dramatically enhanced panel efficiency

Special large ports for wood burning stove gravity connection

Extra sensor pockets for home automation compatibility

DHW prioritised with energy overspill to heating

Condensing gas boiler optimised – controlled return flow temperature

Heat pump optimised and compatible with other heat sources

Heat pump COP raised through extra daytime running

3kW immersion for backup heating

4 stage safety system for energy control

A mix of under-floor heating, towel rails and fan-coils can be used

Fan-coils and a suitable heat pump can give air conditioning

Find more essential reading on my e-book, an easy download on Amazon. Over 100 detailed tips for less than the price of a pint!

‘Dream House – Down To The Details’

…. and check out the LIST OF POSTS for more like this

Eco Heating News

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Heating News  Jan 2016

An Eco-house restoration case study

New Controller from Z-Wave and a chip upgrade

Clearview stove price check

Ultra cheap LED bulbs

£4 automated kettle

Eco restoration case study

We were constructing our dream house for a family of four. A total roof off renovation and extension of a 140 square metres, stone-walled Italian farmhouse in the hills near Città di Castello.  Heating is a big issue in Italy and having rented a farmhouse for a number of years we knew first-hand how brutal the winters can be!  This is how we met that challenge.

Judging by the freezing house we rented and friends’ houses, we knew we had to avoid the miserable conditions they suffered along with huge heating bills.  Insulation was an essential first step and with the help of architect Marco Carlini we built a ventilated roof that was almost over the top in efficiency terms, but then there is no such thing as too much insulation.  Plenty of insulation under the floors ensure that the heating is pretty responsive – by making sure it goes up into the tiles and not down into a freezing cold concrete slab underneath (yes, heat travels in all directions!)

Heating with gas was never an option, a pellet stove offered expensive fuel with noise and maintenance. What we needed was to burn wood (the cheapest source of energy) and add free solar power to that; how to integrate all these things workably and efficiently was not at all clear but fortunately eco-heating consultant Patrick Littlehales stepped in with a total solution which was clearly going to tick all the boxes.  After a whole day in a heating seminar all the clouds lifted and the final system was not only obvious but remarkably simple too.  Basically it’s a big tank of water (Specflue 500L heat bank) a Clearview 750 stove with back boiler and an extra big set of solar panels. Probably the one thing that brings this off is matching the overlap of the power curves as winter heat (wood) gives way to summer solar – when the curves overlap you don’t need another source like gas to fill in.

Patrick is a great exponent of ZERO COST heating and we loved that idea. It was simple enough; photovoltaic solar panels on our new roof would make enough money to pay for wood and minimal electricity.  To catch a good tariff Marco Tufi from IWT Engineering put the panels on the old roof and then they were later transferred to the new roof a year later when it was ready.

Going into our second winter the system has met all our expectations – we just love it.  The 14kW stove is a focal point and is a joy to operate. It easily heats the house (radiators/UHF upstairs and UHF downstairs) and provides masses of hot water. The tank has a 3kW immersion heater and I fitted an additional 2kW one to use some of our free electricity.  The oversized solarthermal array has been startlingly successful.  Three panels from Sunerg sit on the bank by the house (fantastic bargain – thank you Patrick). They are angled steeply to catch the winter sun and tame the fierce summer sun; the resulting flat and wide power curve gives remarkable performance in the shoulder months, even into January.

Living in the countryside brings the risk of being stranded in the snow and power cuts – a potentially deadly combination.  Our stove and tank are simply connected with no pumps so we can cook on the top (we do anyway) and keep warm come what may.  Not many homes have that level of security. There’s no risk of our heat bank overheating since it thermosiphons perfectly to two upstairs radiators – slowly dumping the heat – an additional, power-free way of heating!

Was it hugely expensive?  Yes and no.  The up-front equipment costs were certainly weighty but offset by the ease and speed with which the heat bank and all its pumps etc. was installed. In this respect it was practically free.  The fact is that the investment will be paid back relatively quickly (Photovoltaic the longest in around 7 years) and after that we’ll live almost cost free in our dream house – what’s not to like?

 

A new controller from Mi Casa Verde as Z-Wave gathers pace.

Mi Casa Verde have just released their Vera Plus smart home controller for a mere £140.  For anyone considering starting a home security system, with the option of a host of home automation features thrown in, this is really good news.

Vera Plus lets you easily set up, monitor and control lights, cameras, thermostats, door locks, sensors, alarms, smoke detectors, lawn sprinklers and more from practically any brand. VeraPlus supports 1400+ devices from all major brands and works with many popular devices using Wi-Fi, Z-Wave, ZigBee, or Bluetooth.  All this is unified under one single app which runs on any tablet or smart phone.  You can buy Vera Plus from http://www.vesternet.com/ and get plenty of advice at the same time.

Z-Wave itself is moving on with the release of a third generation of the chip found in every device. This gives better range between devices which in turn extend the range further in a meshed network.  Extended range means that security sensors can be placed further out from your house to mark out your first perimeter.  I love the idea of having a table lamp give a subtle flash when guests are arriving – it’s not all about the burglars.

Multiple functionality is emphasised in the new chip so now if you buy a motion sensor it is likely to measure temperature and light levels too; all useful features when controlling lights or heating.  Another example is the Fibaro flood sensor which includes a tilt sensor (so you know if someone moved it), temperature sensor, a siren, a light, a built in Z-wave network range tester.  If you leave your house unattended for long periods, you might feel happier if you had popped one of these on the floor.

There are now 250 firms making Z-Wave products, so you might start off with a controller and a couple of sensors, just to get the hang of it, but after that adding more features is a never ending journey.

Clearview 750 prices.

I’ve had a couple of enquiries recently so here is the latest quote from the factory for the ever popular 750 flat top with the 7kW back boiler.  N.B. When I’m supplying tanks and stoves I always try to round down the prices and they come with loads of free advice too.

Stove              £1,782

Back boiler       £312

Colour               £60

UK delivery        £49

Total                  £2,203

You might ask why the Clearview is so popular when it is also rather expensive.  Well there’s robustness for a start. Folded up quarter inch plate is tough and indeed rather weighty; it takes 4 strong men to move one.  Then there’s the clip in – and easily replaceable –  stainless back boiler. A leaky, crack prone cast iron stove with integrated boiler might save a few bob now but you might have to buy a couple more during the lifetime service of a Clearview.  A cracked stove could ruin your floors and rugs and leave you without heat for weeks. A fate to be avoided at all costs. Personally I prefer the plain looks and the huge glass doors giving a great view of the fire.

 

LED light bulbs – cheaper than cheap!

Take a look at http://www.trillion.co.uk and check out a range of LED bulbs starting from £1.50!

Now that’s just as cheap as any other type of bulb so there is no reason to hang back.  And yes you should bin any other bulbs immediately in favour of LEDs which consume about a tenth as much as an incandescent bulb.  An old 60 Watt bulb running 2,000 hrs a year (if it lasts) will cost £26 to run in Italy and £14 in the UK so the cost of the bulbs is becoming trivial compared to the running costs.  I’ve just bought a shed load of bulbs from Trillion and they seem fine with the warm white ones (2,700K) a good colour.

£4 automated kettle

Do you make the early morning tea?  Don’t you hate standing around in the cold waiting for the kettle to boil?  £4 at Amazon for a square timer plug will change your life.  Last thing at night, fill up the kettle and leave it turned on. Set the timer to come on when you wake up and only get out of bed when you hear the kettle click off. Nice.

If you’d like to talk about heating, cheap pool pumping, solar panels, stoves, tanks and everything else please use the contact form here.

…. and check out the LIST OF POSTS for more like this

DIY heating system

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click to enlarge

click to enlarge

 

 

Simply the best

Could it be that the very best high performance ecological heating system is also less expensive than a conventional system? Could it be so simple and quick to install that you could do it yourself?

Yes absolutely, is the answer to both questions if you use a Specflue Xcel heat bank which, in my opinion, is still the best available.

It is DIYable because all the pumps and wiring are already fitted to the tank so all the techie bits are done for you; one of my plumbers says he can fit one in a day.

Because it is an open vent system it is absolutely safe and anyone is allowed to install it.

 

I could go on forever about why it is the best high performance system but here are the main points:
Stainless steel tank will probably last a lifetime – I prefer the 500 litre one.
Solar panels and woodburning stoves are properly integrated.
Heat pump connections, if required, are sensible and prevent destratification.
Condensing gas boilers run in condensing mode all the time and deliver their full power.
Recovery times are almost instant due to stratification.
Domestic hot water is pure, pressurised and plentiful enough to equal 4 combi boilers running at once.

You don’t even have to install it all at once.  Just keep adding the next bit when time and funds allow.

See here for a brochure http://www.heatweb.co.uk/uploads/files/Xcel-HEATBANK.pdf

I have installed many systems like this. In the days when solar PV gave good returns some of them were ZERO COST for all energy and my own house still makes a profit of about £1,000 a year. The system has been refined over the years and now there is even a special factory version of the tank incorporating a few of my favourite tweaks. I am also very particular about the way it is installed and the thermal characteristics of the house are modeled to make sure transmission matches power etc. I am also very picky about wood burning stoves; you’d be amazed how many people buy the wrong one.

If you are interested in having a go then you can depend on me for lots of advice and supply of a matched set of the heat bank, stove and panels in the UK and across Europe. I try to round down on factory prices and, within reason, give free advice so there is no better way to do your project.

Just use the contact form below to get going and I look forward to discussing your project with you.

Like what you’ve read? Find more essential reading on my e-book

‘Dream House – Down To The Details’ here:-

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Heating News – Autumn 2015

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ENGLAND FRANCE ITALY – Transcontinental Edition

Heating consultancy – England, France, Italy
England and Italy are covered so if you need a stove and a heat bank just get in touch, wherever you are, and I’ll get them to you. My usual transport goes from England to Italy every 2 weeks via France so sensible heating is equally available there. Just fill in the contact form below and we can start to chat.

Heating – Not too late for this winter
A system makeover might seem like a daunting prospect but it can often be as simple as connecting a new tank in your technical room to a few pipes that are already there. The most essential connection is to the wood burning stove; all the other power sources like solar and gas can be added later. There is an immersion heater on the tank to provide backup power if it is ever needed.
A heat bank and stove can be shipped out in about 6 weeks and installed in as little as 2 days.
Not only will your heating bills reduce dramatically but you’ll be cosy and in most cases safe from power cuts. If you were snowed in for 2 weeks without power would your existing system give you heat and cooking facilities? System continuity in a power cut is one of the most important considerations when designing rural heating systems.
Make sure you are safe and comfortable this winter. There is a contact form below.
Special offer on Solar panels
If you buy a stove and tank together I’ll arrange solar panels at trade price – like a big 3 panel kit with pump, controls and fluid for €2,000 + IVA. This is top quality Italian kit at a spectacular price especially as it‘s in Euros.
If you are in the UK or France I’ll do a similar deal and get the panels sent out to you from Italy.
(Subject to supplier price change)

Italian farm house scores a ‘C’
We’ve had the Energy Performance Certificate done on our Italian farm house as it’s up for sale. All the eco systems fitted to the house were officially vindicated by an unusually high ‘C’ rating, narrowly missing a ‘B’, so this proves that old stone houses can be efficient. Apparently the energy rating is an important factor as far as house buyers are concerned and quite rightly so as the wrong systems can cost a fortune to run.
Briefly, the spec. that achieved this was:
Wood stove (Clearview 650) with back boiler
Specflue heat bank
Wet solar panels
PV solar panels
Underfloor heating
Insulated roof
Double glazing.

The whole energy package actually returns a profit every year but we were still relieved that the applied criteria gave a respectable result.

If you’d like to talk about a high performance heating system like this please get in touch using the contact form below. Many versions of the system have been fitted in Italy and several refinements have been added to make it a well honed product known to the supplier as ‘The Italian Job’.
UK energy costs
Gas Gas Gas! If you live in the UK and have access to town gas you have enviably cheap energy. About 3p/kW.hr in fact which means a big 28kW gas boiler costs about £1 an hour to run and 50p for the typical smaller boilers. Knowing that winter lasts for about 200 days gives you a guide to your potential gas bills; 4hrs a day = up to £800 down to £400.
The exact cost depends on the boiler efficiency of course and a condensing boiler will get around 93% (versus as bad as 75% for an old one) but – and here’s the rub – only if the temperature of the return water is low enough to enable the latent heat to be condensed out of the exhaust gases. Upping your efficiency to 93% will save about £280 a year so the boiler is a good idea but it will only return a good result with low return temperatures. The best way to guarantee this is to fit a new tank or, to be specific, a heat bank like the one from Specflue. This stainless steel tank has a long list of benefits, such as integrating solar, wood stoves, under-floor etc but with regard to gas use and hot water delivery it is particularly impressive.
The gas boiler is directly connected to the tank (i.e. no coil) and can deliver full power to hot water to give fantastic recovery times and also continuous use of multiple outlets rather like an overpowered combi-boiler. The return temperature is managed and always correct for condensing mode. Hot water is extracted via an external heat exchanger so the hot water is fresh and pressurised so you can fill the kettle and saucepans with hot water. The pressure you get from your hot taps will now be the same as your cold taps which will put a bit of zing into a previously dribbly shower.
Don’t be put off by last winter’s bad press on condensing boilers – ‘Thousands left without heat in cold snap’ etc. Plumbers were quick to blame the kit but it was the condensate drains freezing and this problem can be bypassed with a break in the tube; the water drips into a funnel and any overflow is caught by a small plastic bowl.

UK electricity.
I used uSwitch to get a deal for 12.251 p/kW.hr after an informative chat with one of their advisors. A £400 annual saving so well worth the cost of a phone call. He will also tell me when a better rate comes up for a free switch to another provider..
It was interesting to note that Economy 7 at 6.232p/kW.hr was still twice the price of gas so the immersion heater is pretty much redundant as is economy 7 itself in most cases. The exception would be an air source heat pump where, despite a poor night time COP due to low temperatures, one would still be running a little cheaper than gas. The all electric eco-house is a possibility then.
UK electricity is almost half the cost of Italian electricity. As a rule of thumb every 1kW for 8 hours a day will cost you £1 (£365 a year) and this could be near your current use as a power meter usually reveals background consumption of around 1kW with a few lights, fridge and computers.
Replacing a 60W bulb with a 10W LED saves 5p in just 8 hours (£18 a year) so chuck all those old bulbs in the bin NOW and remember those curly CFL bulbs are not comparable so go straight to LEDs.

Eco house design

click to enlarge

click to enlarge

I was thinking about a small but overtly modern eco-house design a while ago and realised that it could not be smaller than the panel area required to run the small air source heat pump on a winter day. So the design is basically a big set of panels with a small house underneath. A 6kW array would be good for just over 2kW, just enough to run a small ASHP which in turn would be able to heat the well insulated house. Here is a sketch of what the house could be like. Using modern building materials it would be unusually low priced for the amount of space provided.
See the full article here
https://originaltwist.com/2015/05/20/eco-house
Comments welcome.