Using a Wind Turbine to supplement a conventional oil fired central heating system

[David Hansen]

On 14 Mar 2006 11:48:17 -0800 someone who may be [e-mail] wrote this:-

What is the power of the boiler? I suspect that even running at

1.4kW and with 100% conversion into heat the turbine will not provide much supplementary heating. It may still be worthwhile though.

Wind is available all through the day and night. It seems a pity to waste it when the heating is turned off. This implies storage of the energy. One way of doing this would be to install a heat bank and have an immersion heater powered by the turbine as an input to this. The immersion heater could use dirty electricity and so you could use a relatively cheap turbine. The boiler would be another input. Perhaps there is also a good source of fuel that wouldn't be too difficult for your mum to handle that could also be used as an input to the heat bank. Some form of peat perhaps? This would mean that all the sources were being used for hot water and space heating.

Alternatively the turbine could charge batteries, which would supply most loads in the house via an inverter. Only when operating big loads would electricity be drawn from the external supply.

Is there running water nearby? If so a small scale hydro system might be useful, which would produce electricity for use in the same ways.

Lastly, unless the sky is constantly black with clouds solar water heating might be useful. Again this could feed the heat bank. Evacuated tubes still perform well in cloudy conditions.

I take it the house is insulated, especially the walls and roof. That should be done before anything else.

If you ask in uk.environment you might get a few more ideas.

[meow2222]

Now theres what I call a challenge.

NT

[David Hansen]

On 15 Mar 2006 15:20:20 -0800 someone who may be [e-mail] wrote this:-

I don't call it a challenge. However, doing this involves ductwork, fans (probably) and control systems. What that means is that it is not as simple as cutting a hole in the side of the house and what that also means is that there are some costs and energy inputs to consider.

Barns are (generally) different to houses.

[meow2222]

Sorry, but this is nonsense.

1. Most houses do not have only one room with a south facing wall, it is more normal to have 2 or 3 on one floor, and 2 on the other. That makes 4-5 rooms heated directly, or about half of the house typically.
2. Even if no circulation at all were used, a solar panel could still contribute over half the heating use.
3. Over half because there will be air mixing regardless of what you do. Add the fact that any houses are open plan, in many the internal doors get left open, and in many cases part of the south facing wall supplies a corridor, and you're well over half. Patyback is of course still good with less than 100% heating replacement.
4. Then add use of the comfort zone, the fact that the solar heater can take those rooms up to 23 and still be comfortable. This temp diff will cause heat movement from warm to cooler rooms.

Etc. The assertion that ducts are needed is a flying pig.

NT

[David Hansen]

On 16 Mar 2006 06:48:50 -0800 someone who may be [e-mail] wrote this:-

So you claim.

That rather depends on the house. Many houses have no south facing walls, as they are part of a terrace. If they do have south facing walls then they may have the number of rooms you claim facing south, but are more likely to have one room on the ground floor and one or two on the upper floor. Perhaps a quarter of the house typically.

Such panels could indeed heat any suitable rooms, in the right weather. Whether that was over half the heating use or not depends on the house, but I suspect it would be rather less than half for nearly every house. A barn designed specifically for this form of heating could manage more. Still I'm pleased we have now gone from whole house heating to supplementary heating.

One needs large volumes of air to convey the same amount of heat as a small volume of water. That is why air ducts are large and heating pipes small.

To heat a room it is not enough to just leave the door open and hope for the best. One would need a means of supplying warmed air to the spaces concerned and removing the cooler air. One could design a house around such a system, but it would be difficult to fit into an existing house.

So you claim. I disagree for the reasons I gave above.

Ditto.

[meow2222]

and those are relevant?

You can do either, but solar heat normally coexists with fuel heating for obvious reasons.

Even a half dead person can work out how to circulate air without running ducting.

If you want to learn about it alt.solar.thermal.

NT

[AJH]

At the risk of being run out of uk.d-i-y as an ecofreak how about a dual use for the wind turbine. We know in the absence of net metering it is difficult to get the best from electricity generated by a homer turbine so could we configure it to have an electro magnetic clutch that could either turn an alternator or a refrigeration compressor, such as one for a car's air conditioning? How much power do these draw? This gets around the lossyness of small alternators. Alternatively we could use the electricity to run a refrigerant compressor.

One thing about the air conditioning compressor is that it should shift about the same amount of heat per revolution and not be too fussy at which speed it turns.

A quick calculation seems to suggest that heat pumped at a COP of 3 by a directly coupled turbine and dumped into a thermal mass could be several times more valuable than generated electricity where no battery storage is available and there is no provision for net metering.

AJH