Is it possible to be 100% off grid for a maximum capital outlay of £15k? Location - rural, exposed south facing half acre plot in Scotland with am average wind speed of 6.1.

What renewable technology would you use to provide all your heating and power needs for a 4 bed house? If it can't be done for less than £15k how much do you think it would cost?

Insulate and get airtight then work out heat loss then think about how much solar heat you can use then think about an inter-seasonal thermal store (needn't be expensive) then see what you maximum base load will be then look at reducing that then size your generation or storage capacity.

we cant say yes or no without a lot more info.

No. Stuart but it really depends on how frugal you want to be when the wind does not blow. I know someone offgrid (electric )with just a 2.5kw proven but i think they are using bottle gas etc for cooking.

To be truly off grid for energy, you will need to spend £25,000 if you self install or £35,000 + if you use installers. You will need a tri or quad-hybrid mix or massive batteries. Tri-hybrid would be wood, wind and solar (active, passive and PV). Quad-hybrid would include some water power input.

Lots of hands-on too. If you are in a really windy site than a large wind turbine 6 or 15kw will give you a good proportion of your annual power but not complete.

Frighteningly rough breakdown.
Wood boiler and system - £7,000 self install or £12,000 installed

Inverter, batteries etc for electricity - £4,500 self or £6,500 installed

Wind turbine - 2.5kw £16,000 self install may not be an option

Micro water turbine if water available (include for pipes, ponds and lots of wasted time playing with water) - £4,000 self install or thousands and thousands if installed

Solar PV - how deep are your pockets? best technology though so budget as much as poss - say £5,000

Solar thermal - £2,500 self install or £4,500 installed

Solar passive can go into your design at little extra cost.

Dont forget the logging equipment and the land needed for planting trees - grants available though

But it is the best fun you will ever have though and I've got energy coming out of my ears at the moment. Energy price increases - what are they?

Sounds like a good name for them!

Thanks for the responses! I had thought that it may run into the low £20k's but had hoped for less! Keith - can you expand on the ash trees in a semi-circle??

The semicircle is to protect the other ground from the harsh north weather and create a suntrap to help warm the ground. As Dazread has said some hazel in the outer edges will grow less high so would allow low morning and evening sun in.

Have you taken a look at the Skystream 3.7 wind turbine from Southwest Windpower Stuart. It looks really quite economical and could help you keep nearer your budget. The guide prices seems to be about £6500 + groundwork. That's about half the installed price of the Proven! (Plus batteries etc of course).

Posted By: chipedwoodAlso I wouldn't recommend any solar equipment in the UK as it is not efficient enough to pay for itself even in the long run.

But I guess you are comparing with the cost of fossil fuels and perhaps you haven't appreciated that peak oil is probably in the past (or if not will be in a few years at most) and peak gas isn't going to be far behind and peak coal might be as soon as 2025 -- annual 10 to 20% fossil fuel prices rises are probably going to be the norm for the next few years...

Posted By: StuartBstephendv - 6.7kwh seems very high for a 2 bed house! We are currently burning 7.9kwh in a not particulary efficient 4 bed home, I would hope to get this down considerabley with a new build.

I think you're getting mixed up between kWh and kW - 6.7kWh is very little over a 24 hour period - equivalent to less than 3 100W lightbulbs. At the electrical rate I pay, that would be equivalent to around Can$140 a year. If, as I suspect, your load is 7.9kW, you'd consume around 190 kWh in a day which sounds more like it for an inefficient 4 bedroom house in winter in Scotland!

Paul in Montreal

Posted By: StuartBPaul, you are correct, excuse my maths. It was 70,000kwh for the year.

Wow, that is an astounding electricity consumption! You're right that it's not very efficient! We scrape by on 25,000kWh per year in a much colder climate than you for what is probably a similar sized house. What form of heating system do you have?

The original poster was talking about lighting and appliance consumption only so 6.7kWh per day is not too bad. My baseload is around 10kWh per day (measured during the period between the heating season and the cooling season) - and a good part of that is the computer equipment.

Paul in Montreal

Posted By: StuartB4,681mWh for electric and 22,300 kWh for gas which is how I got to 70,000 for the year. Does this sound excessive/incorrect anyone?

I'm not sure how you summed these to 70,000kWh. The sum is 26681kWh which is much more reasonable.

Posted By: StuartBCanada is definitely somewhere I could live. The quality of life is so much higher than the UK. Lovely hot summers too which I guess helps you get through the freezing winter!

Yes, the summer certainly make up for the winters - though last summer was not particularly hot, though it was sunnier and average and also wetter too - though most of the rain was at night. It gets as much above freezing in summer as it goes below freezing in winter - it's like there's a big +30C / -30C switch that gets thrown twice a year

Regards,

Paul in Montreal.

I'd just like to reiterate getting your consumption down as the first place to start.

I'm sure you can drastically reduce your consumption below those values! Just for info, here's how we do it.

I have a 1930s semi (110m^2 total floor area) in Sheffield and this year the house has been occupied 24/7 due to the arrival of our baby in Jan 08. We have used around 6000kWh of gas and 5.2kWhr/day of electricity in the last year - and we have an electric cooker (not my choice, I'd like to add!). We have a new combi boiler and a wood burning (5kW) stove.

Central heating is only on for around 45mins in the morning and only ever on in rooms that we use. It is on for around in hour in the evening, but most importantly of all, the thermostat is set to around 13-14 degrees. It gets the kitchen warm enough for breakfast and the stove is then lit which keeps the lounge at between 17 and 20. The stove keeps the dinning room to around 16-18 degrees as well.

So I would think it is probably possible to significantly reduce your energy consumption and as a result, significantly reduce some of the costs of your renewable energy generation.

Posted By: tonyInsulate and get airtight then work out heat loss then think about how much solar heat you can use then think about an inter-seasonal thermal store (needn't be expensive) then see what you maximum base load will be then look at reducing that then size your generation or storage capacity.

That should be on a banner across the top of every GBF and AECB page! Says it all.

Posted By: MarkHpmcc - we chose to have Warmcel blown behind our plasterboard between the timber frame. We already had 25mm of EPS (and then a 75mm gap). This seems to have been effective (we think the walls now have a u value of 0.35 or better), and although just as messy as ripping off plasterboard to fill the stud work with rigid insulation, it was about 20% of the cost if my memory serves...

Interesting - from various conversations and general reading I had formed the impression that blown-in insulation wouldn't work for timber frame. Could that be because there is sometimes a vapour control layer outside the studs, which would trap moisture and cause rot?

Also, for some reason I thought there had to be some sort of gap immediately behind the plasterboard to allow for electric wires and other services. In my house making such a gap that would mean ripping the plasterboard off anyway.

Did you fill up the whole space between the foil back of the plasterboard and the wood on the outside of the studs? Presumably you drill a hold in the plasterboard and spray it in? If so what happened to stuff like wiring - just trapped inside the insulation? Warmcel is supposed to have effective fire suppressants, but I wonder about fire risks from loose electrical connections...

Sorry for so many questions - I've not seen a good explanation of this elsewhere.

Posted By: StuartBIs it possible to be 100% off grid for a maximum capital outlay of £15k? Location - rural, exposed south facing half acre plot in Scotland with am average wind speed of 6.1.

What renewable technology would you use to provide all your heating and power needs for a 4 bed house? If it can't be done for less than £15k how much do you think it would cost?

You could go down the biomass CHP route especially as it is eligible for ROC's and RHI when it comes in.

10kw solution for $16995 20kw for $25995 plus shipping and import duties.

http://www.gekgasifier.com/gasification-store/gasifier-genset-skids/

Posted By: fostertom

Posted By: renewablejohnWhat renewable technology would you use to provide all your heating

I answered you that but you poured scorn on it, poss because it wasn't a bolt-on 'technology' but something more integral in the (re)design of the house's fabric.

Fostertom

Just to clarify it was StuartB who posed that question even though the system suggests that it was posted by me.