11kw Turbine powering elctric boiler for heat & water ?

[med777]

Hiya,

And apologies if this is covered and I have missed it - Im new here !

We are looking at installing an electric boiler to supply our hot water & central heating and an 11kw gaia turbine. We are in open countryside, no obstructions, 800 feet above sea level and on the edge of Whitelees Windfarm ( so a good site)

Is this do-able ?

Miriam

[kenneal - lagger]

Welcome Miriam.

Although this may make sense economically I hate the idea of installing electrical production facilities and then using that valuable electricity for heating. It's a waste of a very precious resource.

Have you looked at super insulating your house instead. It's quite feasible to reduce your energy bills by over 80% and make your house far more comfortable by a comprehensive scheme of insulation. I've done it on 1970s properties and it would be easier to do on an older property; 90% would be possible. The great thing about insulation is that there is virtually no maintenance and no moving parts to go wrong.

What's the point of putting an expensive heating installation into a leaky old sieve? No matter what the temperature you achieve it still won't be comfortable and could even increase damp problems.

[biffvernon]

Insulate first of course.

Then, you may find that it is financially better to sell the electricity to the grid and buy other fuel such as logs to heat the house. Electricity is always going to be an expensive way to heat your home even if you generate your own. Remember to take into account opportunity costs.

[adam2]

Electric heating powered by a wind turbine is certainly possible, but as others post may not make economic sense.

If the premises has a grid connection, or if one can be affordably obtained, then selling the electricity to the grid, and useing it in your home for higher value applications probably makes more sense.

If however no grid connection is available, then wind powered electric heating can make more sense.
If off grid and desireing modern convieiences, then a wind turbine will compare very favourably with a diesel generator.
It can then make sense to select a much larger wind turbine than at first seems sufficient.
An 11KW machine wont cost 11 times as much as a 1KW one. The 11KW turbine will charge batteries even at low speeds, permitting of a smaller battery, or more days reserve from the same size battery.
The large wind turbine will in windy weather produce a considerable surplus of electricity beyond that required for lighting, IT, refrigeration etc. This surplus can used for heating and domestic hot water at relatively little expense.
It is unlikely that wind power alone will suffice for heating a home, some other source of heating such as wood, coal, or bottled gas is desireable.
A diesel generator with heat recovery is another option for calm weather.

If you fear TEOTWAWKI and wish to be independant of the grid then similar arguments apply. Being off grid when a grid connection is available should however be looked upon as insurance or a doomer prep, and not as a wise investment in strictly financial terms.

I would not attempt to power a standard electric boiler from a wind turbine as these boilers have almost no storage for even a short calm spell.
A better plan would be a very large hot water tank with a number of heating elements and an automatic controller that adjusts the load according to wind speed.
This stored hot water may then be circulated through conventional rads, or used for underfloor heating.
A couple of days reserve is easily obtained, and up to a week is possible with a huge tank.

[med777]

Thank you people !

Our farmhouse is over 2ooyears old , insulation is maxed out and it is very wind and watertight. We are connected to the grid and already have solar PV panels and have had a very successful first year from the FIT & reduction in our electricity bill.
But it is a very large & long house and heating it with Oil is costing over £5000 a year- so u can understand why I want to be energy independent !

We have done the sums and financially the turbine seems to be a much better investment than the money sitting in a bank. We can expect a very good return from the wind as we are a prime site - well in excess of 40,000kW/h per year
I realise that my location is quite unique and this is probably why it has been so difficult to find information on electric boilers powered by wind turbines.
If we do go ahead with this I need to be sure that an 11kW turbine will provide the power we need to heat this home.


Thanks

Miriam

[Bandidoz]

A better plan would be a very large hot water tank with a number of heating elements and an automatic controller that adjusts the load according to wind speed.
This stored hot water may then be circulated through conventional reads, or used for undfloor heating.
A couple of days reserve is easily obtained, and up to a week is possible with a huge tank.

Yep - would make a good dump load if off-grid.

[adam2]

An 11 KW wind turbine is most unlikely to meet the entire heating demand of a large home.
It should however meet a substantial percentage of the heating demand and greatly reduce the oil or other fuel used.

I would retain the existing oil burning heating for calm weather.
Despite future concerns about price and availabilty, oil still has a lot to commend it, much cheaper than electrcity, readily stored on site, and useful for other purposes.

A few tons of oil is a vast reserve of energy, that if eked out by wind, solar, or firewood could last many years, in case ot TEOTWAWKI.

[med777]

An 11 KW wind turbine is most unlikely to meet the entire heating demand of a large home.
It should however meet a substantial percentage of the heating demand and greatly reduce the oil or other fuel used.

I would retain the existing oil burning heating for calm weather.
Despite future concerns about price and availabilty, oil still has a lot to commend it, much cheaper than electrcity, readily stored on site, and useful for other purposes.

A few tons of oil is a vast reserve of energy, that if eked out by wind, solar, or firewood could last many years, in case ot TEOTWAWKI.

We fully intend keeping the oil, if for nothing else - for power cuts. I have a wee genny and can keep my kitchen/lights/hotwater/oil boiler/fridge/freezers and last but not least TV ticking over - just a matter of planning in advance. ( and useful in case of a sudden TEOTWAWKI ! )

Thank you for your advice re the turbine and the heating. What I need to do now is find out about electric boilers - not something I know anything about - yet ! lol

Miriam

[kenneal - lagger]

When you say that insulation is maxed out and you are still spending £5k a year on heating it sounds as though your insulation is badly installed or there is not really enough. Do you have external wall insulation? How thick is your loft insulation? Are your floors insulated?

[RenewableCandy]

Hmm yes £5k is rather a lot isn't it? Perhaps they just have a huge house?

[med777]

Its a rubble construction single storey farmhouse, walls approx 3' thick strapped & lined. part of the house has wooden floors, they have a thermal barrier, heavy duty 5* underlay, remainder is concrete again with barrier & underlay and a mix of tiles and carpet. Windows & doors, dble glazed and all with heavy curtains & thermal liners. Loft insulation is about 300mm and all the pipes lagged.
Oil boiler serviced every year & runs @ min temp(60) always and is on a timer - couple of hours in the morning and hour mid day and then from about 7.30 till 12.30am. Radiators all have thermostats and all tuned in for each room & its use. During the summer - usually the heating is off with occasionally an hour just before bed.
The house is one room wide, seven rooms long plus a barn conversion that is our lounge (which was a 'from the bare bones' job... so there is mega insulation.) It is a very long L shaped building.
We live at the top of a hill- just under 800 feet, central Scotland and it is windy.
So all in all, I think we have all the usual suspects covered... it is a large house... room size is approx 16' x 16' - with the barn being barn sized ! lol

Miriam

[kenneal - lagger]

By insulating on the inside you're lost the benefit of all that lovely thermal mass and you've not put in insulation to the max, you've tickled the surface. Any house insulated to the max would have a total thickness of insulation of 300mm of fibre or 200mm of PIR foam board to get an insulation value of about 0.1. This would go down to the footing to provide an insulated perimeter, although with a stone house I suspect the foundations are very near the surface. The roof would be maxed out at 450mm of fibrous insulation or 300 of PIR board.

If you've insulated on the inside you've probably only got 50mm of a foam board which will give you a u-value of about 0.35 to 0.4 depending on the type of stone or 0.5 or more with Rockwool. This internal insulation will also cause a build up of moisture, interstitial condensation, within the walls which will lower the insulation value of the stone even further. The roof should be sealed to stop wind penetration, which will substantially reduce the value of a fibrous loft insulation, and fitted with a breather membrane.

One man's "mega-insulation" is another man's architect's Building Regs minimum. Do your insulation levels match these values? If not I would ask your architect/designer why not? I'm sorry to sound so cross, Miriam, but large "Grand Designs" builds always waste energy, both in the building and the heating, and can never be energy efficient. The fact that you can't afford to heat the place but can afford to install a load of expensive equipment to remedy the poor design suggests a breakdown in the design process somewhere.

[emordnilap]

What k's saying is a woolly hat works well. Thing is though, it has to be on the outside of the head.

[kenneal - lagger]

What k's saying is a woolly hat works well. Thing is though, it has to be on the outside of the head.

[Tarrel]

Its a rubble construction single storey farmhouse, walls approx 3' thick strapped & lined. part of the house has wooden floors, they have a thermal barrier, heavy duty 5* underlay, remainder is concrete again with barrier & underlay and a mix of tiles and carpet. Windows & doors, dble glazed and all with heavy curtains & thermal liners. Loft insulation is about 300mm and all the pipes lagged.
Oil boiler serviced every year & runs @ min temp(60) always and is on a timer - couple of hours in the morning and hour mid day and then from about 7.30 till 12.30am. Radiators all have thermostats and all tuned in for each room & its use. During the summer - usually the heating is off with occasionally an hour just before bed.
The house is one room wide, seven rooms long plus a barn conversion that is our lounge (which was a 'from the bare bones' job... so there is mega insulation.) It is a very long L shaped building.
We live at the top of a hill- just under 800 feet, central Scotland and it is windy.
So all in all, I think we have all the usual suspects covered... it is a large house... room size is approx 16' x 16' - with the barn being barn sized ! lol

Miriam

Seems like a heck of a lot of oil. Around 7000 litres per year which, even if averaged evenly over the year, would equate to around 20 litres a day. Probably more like 30+ during the winter. I've been monitoring the consumption of our boiler recently (now relegated to a back-up / support role since we installed a wood burning Rayburn). It's stated consumption when running is 3 litres per hour but, with the boiler thermostat on minimum, it's only running for 2 minutes in 12. So we actually use around 0.5 litres per hour. The boiler is a big Grant exterior job, and our house is of similar construction to yours but not as big (but also not as well insulated - sorry Ken!).

Are you sure no-one is nicking your oil? We were having ours taken at one point. I put a combination lock on the tank and the consumption miraculously went down!

I envy your wind turbine plan. We are not in the right location for one unfortunately.