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Author Archives: originaltwist
Silent gaming PC
Silent gaming PC by Original Twist
What a great time to build a gaming PC. The Intel core i5 8400 presents the sweet spot in terms of performance for money and as it has to have a new motherboard the Gigabyte Z370N WiFi Mini-ITX is a great, and near compulsory, match. The board even has two M.2 slots so you can have SSDs without the untidy wiring. Near to the previous core i7 performance for less heat (and less money), the 65W CPU is even easier to cool with heat pipes.
You might remember the Original Twist silent PC and now this is a gaming upgrade with more space and probably the biggest heatsink tally on the planet.
As before, the corner extrusions are ‘off the shelf’ aluminium extrusions as are the heatsinks where the supplier offers a CNC machining facility for the 6mm heat pipe channels.
This section across the lower half shows a Mini-ITX board, HDPLEX 300W AC-DC and GTX 1060 GPU in position with plenty of room to spare. The heat pipes from the core i5 go above on the same heat sink, same for the GTX 1060 although it could use the space in the centre extrusion for its pipes. With CNC machining it is just as easy to have splayed channels as parallel ones so bending and fitting the pipes will be easier than usual.
The case is like a tall chimney so there will be good airflow across all components, a clear advantage over flat cases with horizontally aligned motherboards. The vertical alignment of the heatpipes gives optimal performance; around twice as good as horizontal ones. By sticking the tails of these pipes slightly below the CPU block there will be more water running back down the pipes – another performance tweak which takes the potential capacity to over 100W.
Heavy duty gamers and clockers will scoff at 100W so just for them ….. a 9 pipe copper CPU block with the pipes running up into back to back heatsinks. i.e. the pipes are clamped between an additional section of heat sink inside the case. So, 9 long pipes running vertically to doubled up heatsinks and the chimney effect even stronger. Actually there’s easily enough room on the heatsinks to fit 11 pipes from a 6 + 5 CPU block – how much power have you got?
The corner extrusions are ready for m6 screws to hold on the open top and bottom plates and the feet, which could be rubber doorstops (well why not?) The perspex side cover over all the connections can be laser cut once the pattern is fixed and that job can be subbed out quite cheaply.
Fancy building one? Fancy buying one? Register your interest below – opportunity knocks.
More on this topic in LIST OF POSTS
Cool fireplace design
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.
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.
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.
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
Alternative to plaster wall finishing
The clean, white, boxy rooms of modern architecture are all very crisp and neat but the reality for the occupants can be that they make for clinical, boring and echoic spaces without much sense of warmth and homeliness. All too often money is spent on plastering which is then covered up. Think long and hard before plastering a kitchen wall before cupboards and splashbacks make that work redundant.
Similarly, there is no need to cover up plasterwork with a fitted bookshelf or cupboards especially double sided ones serving a room on the other side. Hey, you might not even build a wall here let alone plaster both sides, just leave a large opening.
The Original Twist integrated concrete beam system can make a beautifully lit ceiling with wooden beams and boards …. but what about the walls? You might be wondering how to finish the stack of Durisol blocks you built with. The usual plastering solution needs a certain amount of organisation; the first fix plumbing and wiring has to be done and then the plasterer booked for some slot later. From start to finish it could be at least a couple of weeks before the plaster has dried and been painted. Even then there are many things a plain plastered wall does not deliver, so let’s have a look at the Original Twist concept wall and see what extra benefits can be achieved. Here are some ideas incorporated into one picture – it doesn’t have to be this busy.
Basically there are three or four transverse wooden beams fixed to the wall and then panels fit somewhat loosely and quickly onto them. Extra insulation can be particularly easily added at this stage.
This top beam has a rebate sawn at the back to allow the top panel to be held in place then dab bonded to the wall or a top batten. Pictured is a strip of plywood with vertical marks scratched to resemble boards; quick and inexpensive. Strip LEDs are then laid on top of and under the beam and hidden behind the pelmet board – an inverted strip of skirting board would be good for this. Note how lovely the panels will look when the lights go on.
The next beam down has a similar rebate and here the larger panels are pushed up first to hook under the top beam before dropping into place on the beam below. Our top picture shows an example of black ash faced panels with OSB panels fitted on top. The latter can be covered in anything from wallpaper to fabrics and give unlimited scope for decoration; they could even match a TV screen. If engineered floor boards are being used for this section remember that many of them come in 1.2m lengths so designing for that might save a bit of time and not leave any waste.
The lowest section takes on a colonial look with tongue and groove boards under a shelf. The point of this is that wires and pipes can be hidden as can tubes for integrated dust extraction. Fan coil units for heating and air-conditioning can be fitted into this space with the inlet and outlet vents facing down and hidden. If possible the height of this section should be like kitchen cupboards so that doors and hinges can be incorporated and some mini cupboards too. The underside of the lowest beam has a routed slot for another LED strip light which will highlight the lower panel which acts like a deep skirting board.
So there we have it; loads of character, good sound absorption, sensational lighting, lots of utility and all quite easily done by any DIYer.
Internal walls in blockwork can be visually tied in by using the same beams but leaving the blockwork as the finish. Blocks can be painted in different shades before they are laid to make an interesting textured look. Any other wall incorporating a fireplace can be made in exposed brickwork to give a structural element with exposed brickwork on the reverse side. By the time all the remaining areas are covered by glass doors and a bit of wood panelling there may be very little plastering to be done at all.
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. here:-
https://originaltwist.com/2017/02/16/1370/
Heating for your eco-house
For another example of sensible thinking, this time on heating systems, have a look here.
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
Modern floating staircase
DIY floating stairs
How hard would it be to make a modern staircase to embellish your new build house? Not too hard is the answer, as long as you design it to be DIYable from the outset.
This modern staircase is based on two 100×50 HRS hollow steel box beams with chunky wooden treads supported on 40x40x6 bright mild steel angle iron support bars welded onto the beams. If you are handy with a router and a welder (MIG is easy) then the construction should be quite straightforward.
The angle iron bars are completely hidden inside the treads which appear to float without any means of support. Double click the image for a closer look.
The slot shown under the front of each tread is for LED strip lights which can be bought in aluminium channels with diffuser covers. Leave a little space around and under them for cooling and rout out a channel under the angle iron for the wires. You also need a hole through the angle iron and the box section for the wires to pass into the box section, preferably with a rubber grommet. All the wires will go down to the bottom step which will house the control elements for making the lights do all the tricks you can imagine. The stairs lit with any colour you chose will be absolutely stunning.
A bought in staircase like this would cost at least £5,000 – £10,000 so you can afford to sub out some of the work to make it easier and buy any tools you need. The routing work is very repetitious and it would be worth getting a local CNC router on the case; there is only about an hour of machining time and accuracy will be perfect. Get the angle iron brackets cut to length too. There will be many chamfered holes to make so I’d say a pillar drill will be essential.
The Design
Tradition has it that a comfort stair is 7” x 11” for rise and going. Rounding up slightly that’s 180 x 280mm. B.S. regulations give ranges for rise of150 -220mm and 220-300mm for going G. The ratio of rise to going gives an important angle which here would be around 33 degrees and must not exceed 42 degrees. You’ll need this angle to saw off the ends of the beams.
The distance H between your two floor levels will set the rise. Find which whole number divides into H to give a rise R near to 180mm or what you prefer. That whole number is one more than the number of treads.
Tread thickness T. B.S. regs state that a 100mm ball must not pass between stairs or guards so if we say that the open gap between the treads will be 98mm then T = R – 98 or more.
The Going overlap. B.S. regs state that the overlap on open stairs must exceed 16mm but too much spoils the design, as you will see when you draw yours. So tread width W = G + 20 will do for a start.
So the treads will be something like 300 x 80 in section. As for length just bear in mind that stairs over a metre wide must have hand rails on both sides. I think 85cm looks about right.
Length of box beams L. To make life easy you could set the top of the box beam level with the top of the top tread, so; The base of our triangle is (no of treads -1) x G / R and then just use Pythagoras to get the longest length of box…. or, frankly, just draw it and see what you get.
Make a note of all your numbers then make a drawing of the side elevation to scale. Sketchup is perfect for this and is free and easy to use. Note the intersection of the top of the angle iron, the beam and the back of the tread. N.B. Sketchup can repeat copies easily so draw and colour just one tread then copy it upwards by the rise and then across by multiples of the going. You’ll need a jig to position the angle supports easily – draw this too to see how it will work.
The safest way to make the stairs is to bolt the two steel box sections firmly in place using the top and bottom cross members. With a sliding jig, position the angle irons, measuring the height of each one from the floor (to prevent cumulative errors). Tack the angles on and then take the whole thing down to weld it properly. To prevent any distortion I’d weld on a few cross struts then grind them off afterwards. If you can cope with the weight it will be easier to turn it all upside down to screw on the treads before remounting it. Fit and test the lights too.
If you make these stairs I’d be very glad to hear about it and to put your photo with this article.
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. here:-
Heating for your eco-house
For another example of out of the box thinking, this time on heating systems, have a look here.
You really should get the heating right and there are many wrong turns where multiple energy sources are integrated.
I supply heat banks and stoves at good prices and give free advice. Transport is easily arranged for UK, France and Italy. If I can be of help please get in touch using the contact form below.
More on this topic in LIST OF POSTS
Integrated Concrete Beam System
Integrated Concrete Beams
Building with Durisol, Quadlock or any other ICF blocks? Here’s the easy way to do a poured concrete floor.
Concrete first floors are good; low noise transmission, high thermal mass and suitable for under-floor heating. The trouble is the shuttering required is elaborate and expensive both in materials and time and once the floor is poured there is usually more work involved in boarding, plastering and painting. Concrete block and beam systems look easier but you do need to be very organised and get delivery of exactly the right beams and after paying for heavy lifting gear they won’t look like a cheap fix. Again there will be final finishing to do. Plastering and painting ceilings – no thanks.
The Original Twist Integrated Concrete Beam system is so suitable for the self builder that it is hard to consider anything else. It couldn’t be simpler. You make up some hollow beams out of easily sourced planks, put them up in a row, fill the gaps with wooden floorboards and pour. That’s it.
Step 1/.
Make up the wooden beams as shown in this cross section. The blue and yellow bits are your choice of regular timber from your local supplier. The slots sawn out of the yellow sections are for wiring channels and it makes sense to insert the wires while the beam is being assembled. The threaded studding stops the beam spreading when the concrete pours in and is part of the construction with the outside acorn nuts making a decorative feature. Use a spindle moulder or router to round off the edges and then apply your choice of finish after distressing with chain, hammer, belt sander etc. You will see that the yellow sections stick up by the thickness of your floor planks and make a perfectly curved transition between the concrete floor and the integral ‘I’ beams. The rebar at the bottom of the ‘I’ section needs to be held in position prior to the pour and this can be done easily and cheaply with pairs of cup hooks screwed into the bottom plank. Use cable ties across each pair to hold the rebars in. Finally, paint the inside of the beam to isolate it from the wet concrete. The beams are then ready to be placed in position, typically on a one metre pitch (Durisol blocks are half a metre wide) and each propped with one or two Acrow props. If you are using ICFs like Durisol for your walls you should cut out large slots on the inside face to take the beam ends. You might want to pour the walls up to the level of the beam bases now.
Step 2/.
The floor planks can be cut and finished at ground level before fitting between adjacent beams. Now is the time to fit any pockets for spot lamps and take the wiring back towards the slots pre-cut in the main beams. The floor planks need to be strong enough to resist the weight of the concrete without sagging; they don’t need to be jointed together as a layer of building paper over the top will stop any leaks. Unlike concrete blocks they are light and easy to pass up to your helper.
Step 3/.
With steel mesh over the beams and planks the floor is ready to pour. The outside of the Durisol blocks sets the top level of the floor so you don’t even need any shuttering. Once the pour is done and set, the walls and floor are all integrated with the homogeneous ‘I’ sections in the beams giving enormous strength and stiffness. The ‘I’ section parts of the floor could be up to 360mm deep which makes them into a row of significant beams in their own right. At this point the lower part of the house is waterproof which makes for a good working environment from which to finish off the rest.
Step 4/.
Nothing much to do now. Just take down the props then go down to the pub to celebrate all the money and time you’ve saved. There is no ceiling finishing to do, no shuttering to take down, even the lights are fitted and wired. And all this was done with simple hand tools and without waiting for special parts to be delivered. And just look; lovely lovely beams adding character and value to your home.
Notes:
A small spacer between the top of the beam and the floor joists will create a gap to house some LED strip lights. As you have a lovely wooden ceiling you might as well show it off.
N.B. Wood shrinks. A tiny air gap could eventually appear between the concrete floor and the wood floor. A very thin rubber membrane between the floors (instead of the building paper) will prevent any ‘thwack’ as the upper floor is walked on.
Ground floor block and beam – alternative system
Block and beam systems are commonly used for ground floor construction but again they can’t compete with our integrated beam system. Block and beam materials all have to brought to site and then assembled – lots of work there. All those blocks are more gap fillers than strength givers and they are followed by a poured screed anyway. With the integrated beam system you just string out the wooden beams, fill the gaps with plywood and then pour – not only much quicker but stronger too. Use adjustable legs from kitchen units as props, to prevent sagging, and leave them there forever.
With both floors quickly and cheaply constructed and the walls easily made with ICFs it is easy to see that a fully waterproof house up to the first floor could be made in a matter of just a few days. That saves time and money and less exposure to problems with bad weather.
While the rest goes up the internal finishing can start on the first level. Some comments on this here…. and an internal wall cum fireplace design here. … and a floating staircase here.
While this system is great for under floor heating, I’m really not in favour of it for bedrooms as it is a big waste of money for an unwanted result. More on that in the eco-heating link below.
N.B. As usual do your own evaluation for suitability.
Like what you’ve read? Find more essential reading on my e-book, it’s almost free and could save you a fortune. ‘Dream House – Down To The Details’ 101 things you should have thought of. here:-
Heating for your eco-house For essential reading on heating systems, have a look here:
You really should get this right and there are many wrong turns where multiple energy sources are integrated.
I supply heat banks and stoves at good prices and give free advice. Transport is easily arranged for UK, France and Italy. If I can be of help please get in touch using the contact form below.
More house building topics in LIST OF POSTS
Heating News – Autumn 2017
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.
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
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.
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
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.
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
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.