PowerSwitch

My current heating is an oil fired system that must be almost 20 years old. The tank is an old metal one on its last legs too. With oil at almost $60 a barrel, I have decided the time is right to change my heating system before this winter.

My house is quite large (5 bedrooms) and has radiators in every room. We have an open fire in the main Sitting Room that we light a lot in Autumn / Winter. I would like to change this to a back boiler type fire that is linked to the radiators so that the heat of the fire also provides heat to the radiator system too. I had this "solid fuel" heating in my first house.

Before the forum was wiped there was a lot of info.

Can anybody help me decide what form of heating I should install for the PO future?

Mrkinnies is your man...

but for what it's worth, I'd go for a log-fueled boiler, and possibly an additional log burner in your fire place...and then solar water heating, and perhaps even a log-fired oven. This thread might be useful:

http://www.newbuilder.co.uk/forum/index ... 1116374738


Peter.

Blue Peter wrote:Mrkinnies is your man...

If ever a set of questions was made for one person it's these and Mrkinnies !

The old forum you speak of was one of THE most useful I have read anywhere.

Previously I've gone on record with my concerns about wood-fueled domestic heating, not cos I don't think it has value and it is better than gas/coal/oil but because:
1) I fear that popularising wood bruning will make EVERYONE burn wood as soon as other fuels become expensive - wood is the only mainstream fuel you can go out and collect with an axe. We are going to really need the forests we have left - a free for all by the public in need of heat in the depths of winter could complete the deforestation of the Uk in one year
2) It seems (tho I'm no expert) that wood burners are only clean-burning when they run at high temperatures and in a way that speeds the burning process and sends a lot of waste heat up the chimeny. So it's smokey-joe or wasted heat....

I think you need a mix of everything - Solar-thermal, PV and wind all effectively use todays cheap oil to power your home for years to come.

snow hope wrote: Can anybody help me decide what form of heating I should install for the PO future?

Sorry, no good ideas for existing houses, only for new. It is not uncommon that houses become unmodern when times change. How many dwellings from the 1600's are still around and considered modern and useful? From the 1700's? 1800's?

The times coming will have new requirements, and suddenly existing dwellings feel less useful. The smartest thing seem to avoid heating alltogether:

www.earthship.org

You seem to have one in Brighton and one in Scotland.

The real key here is insulation, insulation, and insulation...

With a super insulated house heating becomes much less of an issue.

Walls: -

With a property, which currently has a solid wall construction, go for external insulation and cladding, this will keep the thermal mass within the building envelope allowing a much smoother temperature gradient.

Buildings with cavity walls should have those cavities filled, use either blown fibre or beads if you have any concerns over damp penetration.

Roof: -

Loft insulation must not be ignored, we should all have a minimum of approx. 10 inches of loft insulation by current standards. (Insulation is heavily subsidised at the moment).

Windows: -

Modern Double-glazing is the next step, look for trickle vents in the windows to prevent condensation building up within the fabric of the wall and leading to mould growth. (Look up the dew point to understand the issue of condensation build up in walls).

Air: -

Next is the air leakage issue, ideally all doors should be lobbied, this will prevent your hard earned heat escaping very time you open a door. You can use passive stack ventilation etc to help with this issue.

Orientation: -

Also orientation is one to look for, the highest percentage of glazing should be to the south, use fruit trees for shade in the summer and to allow sunlight to penetrate in the winter. The north elevation needs to have a minimum of glazing and ideally should be buffered by stores, bathrooms kitchens etc. If possible put a greenhouse on the south elevation to act as a solar jacket during the winter.

With all these measures a fully occupied house should require very little heating. Any questions and I?ll do my best to help.

Thanks for the recommendations guys and all the answers thus far are excellent. The question regarding heating the home in a PO world is very difficult to answer since our society is very much entrenched in the whole concept of using fossil fuel. Whether there can be a smooth transition to using solid fuel such as wood and coal (!) in the future is hotly debated, especially amongst us peakniks.

If you want to change your heating to be less reliant on fossil fuels then you have to ask yourself how far down the comfort road do you want to go because this will affect what you install, the cost of doing so and how interactive you will need to be with your new system. For instance, oil and gas boiler systems require very little user involvement assuming there are no breakdowns and you keep a check on the oil level (if you have oil). Solid fuel, however, requires a lot more involvement - you have to light it for a start, then check on it regularly and so on. Basically, the heating of your home will never be the same again if you switch to wood or coal.

As fischertrop rightly says, if one does convert to wood for heating, will there be enough of it in a PO world to go round? Until the carrying capacity of the planet is reduced and the population falls dramtically we will probably face severe shortages of wood in the future. My concern is that we will turn to coal which of course is a climate change issue.

OK, fossil fuels are set to rise, your current system is dying and you've decided to change to alternative heating. Here are the possibilties:

For space heating i.e, to heat your house via radiators then you can choose to install either:

1) A wood or coal (standard multifuel) burning stove with back boiler for connection to your radiators. This will burn logs and coal. This is cheap to install (?2000-3000) but less efficient than any fossil fuel system so burns more wood. If you have a large, poorly insulated, house then this might be an issue. It requires lots of user input. You can opt for a solid fuel burning cooker with back boiler such as a Rayburn, then you can cook as well.

2) A pellet boiler using wood pellets, again with a back boiler. These are a lot more efficient and are automated so require less user input. They cost more, probably around ?3000-?4000 including installation and the downside at the moment is the availabilty of the pellets which is poor. Hopefully this will change, but in a PO world the distribution of pellets might be an issue. There are boilers that will burn both pellets and logs which gets over this problem a bit.

3) A gassifying wood boiler. This is state-of-the-art technolgy with efficiencies of 90%. It burns logs very slowly (burns off the gases from the wood) and so requires very lttle input. It also saves on fuel and you can use local wood. The downside is that you normally need to connect it to a large hot water storage cylinder (an accumulator) which acts like a back boiler and heats your radiators. This pushes the cost up to ?5000/6000+ and you also need space for the boiler and cylinder which is big. Also in a PO world, will such technologically advanced boilers be a good thing or bad? Will there be the constant electricity supply needed to run this boiler and will there be the infrastructure in place for maintenance and parts etc?

4) If you think there will be no problem with electricy supply in the future then you might opt for a heat pump. This is a refrigerator in reverse which extracts heat from a pipe in the ground and puts it into your house. For every kw of electricty used it will give you 3-4kw in your home. These are expensive, starting from ?8000+ and are limited in their output (about 10-12kw normally) so you need a very well insulated house. You also need a lot of space in you garden for the pipe or you can pay the extra cost and fit it in a bore hole to save space.

For hot water (usually called dhw - domestic hot water) you can use all of the above as normal. A series of pumps, thermostats and valves will divert the heat from the back boiler or other chosen heat source and will circulate it around a cylinder of stored water (often called the immersion cylinder as found in all homes with airing cupboards). The simplest system, such as a stove and back boiler (as in 1 above) will heat the dhw cylider via gravity circulation which means that you have hot water regardless of whether you have electrcity because a pump is not needed. If, in a PO world, we have a problem with electricity supply then this will be an advantage. You can also use a solar panel to heat your water. This will cost about ?3000-4000 and will heat the dhw cylinder during daylight hours. This reduces the load on the solid fuel boiler. A solar panel will provide most of your dhw in the summer and some in the winter. You may need to have a different dhw cylinder installed with extra connection points which can be costly (an additional ?500-1000).

If your budget can extend to it then PV (PhotoVoltaic) panels and a wind turbine will give you electricty which can be used for dhw as well as lighting and electric car charging of course. These are however expensive (several thousand each) and you are reliant on decent light levels and a blowing wind.

As you can see there are several options. The issue of what is the best system therefore comes down to budget and how far you want to gurantee your comforts in the future depending on possible PO scenarios. Good insulation, warmer clothes and a few lifestyle changes will probably make as much difference. You also have to take into account what your current plumbing set up is. If you have underfloor heating for instance then changing to the wrong system can present problems, you would probably have to go for using an accumulator or heat pump as in options 3 and 4 above. It is of course hard to advise specifically in this forum. Also, the size of boiler needed depends on your house construction. A typical new build 5 bed house might only require a 10-15kw boiler where as an old C.16th house of the same size with little insulation and badly fitted windows might require 20-25kw. The prices I've given above will no doubt vary also.

Here are some web sites you might want to check out. There are loads more.

Wood boilers, stoves, gassifyers and duel fuel:

http://www.aga-rayburn.co.uk/69.htm
http://www.3genergi.co.uk/index.htm
http://www.econergy.ltd.uk/
http://www.bioenergy.org/

Heat pumps:

http://www.viessmann.co.uk/ (these do solar, wood etc also)
http://www.iceenergy.co.uk/heatpumps.html


Solar panels:

http://www.solartwin.com/
http://www.imaginationsolar.com/index.shtml
http://www.solar-design.demon.co.uk/solar/

Domestic Hot water cyliders:

http://www.albion-online.co.uk/
Click on 'products' on left menu then 'mainsflow thermal store' on right menu. This shows you options for having a cylinder with lots of coils to connect to a solar panel, underfloor heating, wood stove etc simultaneously. These cylinders also deliver mains pressure hot water so you can still have a power shower in a PO world.

PV panels:

http://www.bp.com/sectiongenericarticle ... Id=3060204
(yes this is the oil company BP)
http://www.genersys-solar.com/home.asp

Wind Power:

http://www.almac.co.uk/proven/

Great help - thanks mrkinnies and others. My house was built in 1975, has cavity wall insulation and double glazing throughout - 20mm gap. I will let you know what I decide or more likely come back with a couple more questions.

I do not know if this would be useful to you, it might be to someone so here goes.

Wood-gas, sort of like what an early post was talking about with the system that burned the wood slowly allowing use of of the flammable gases not compacted enough to burn. Build a woodgas generator along with a windmill as to to run an air compressor so as to pump the woodgas into a tank and then use infared heaters thoughout your home that way it would not be a requirement to heat your whole home.

Since no one has talked about this I am dealing with the unexplored. My math said that woodgas should be made with small sticks not whole trees thus we are not cutting down forest but instead removing a fire hazard thus we save our trees. woodgas compared to open fire is about 10 times more efficient going to a direct flame such as a gas cook stove now take that same flame from the cook stove and run it to an infared heater and it is 3 times more efficient meaning by taking the wood breaking it down to gas and running it to an infared heater your more efficient by a factor of 30 or in other words if it takes 7 tons of wood to heat your home for a winter (now do not hold me to this I am still building my monster windmill and have not made it to my processed gas part yet) it should now take about 500 pounds. I know not possible, but my math said otherwise so I myself have got to try it. It has been said on other websites that woodgas was sake enough to be used without an outside exhaust vent. Warning unexplored stuff may not work and every part of what I said is dangerous.

MacG wrote: The times coming will have new requirements, and suddenly existing dwellings feel less useful. The smartest thing seem to avoid heating alltogether:

www.earthship.org

You seem to have one in Brighton and one in Scotland.

http://www.earthshipbiotecture.com/newsalepage.html

http://www.earthshipbiotecture.com/greater_world.html
ha... they seem to have built a very American (but low input) suburb out in the middle of nowhere. Youd still need a car (you're allowed 2 cars per first 500Sq ft of dwelling and one per 1000sq ft thereafter) , otherwise life out there would not be possible.

what are these people actually DOING out in the middle of the New Mexico desert? Where's the village hall? wheres the local shops, agriculture, industry.

This is not a sustainable community. Its a burb built out of recycled bits and pieces with lots of solar panels. Are they going to build their own cars too?

What do they do when they get a toothache? Get in the car and head for civilisation of course. A useful demonstation of low tech possibilities (and some high tech), but no lifestyle shift. Its still just a New Age Levittown.

http://www.earthshipbiotecture.com/Phoe ... xpage.html
Hmm... an interior made of mud and old bottles isnt quite my style.

3 bed 2 bathroom and ONLY a million dollars? SLightly out of my price bracket. Apart from which I dont think Id be able to get planning permssion for one of those where I live, thats if I could even find a plot big enough...

DO they do a high rise version for cities? Up to the 7 floor recommended maximum for post peak oil buildings?

" Two story buildings are generally discouraged."
hmm well thats not going to work too well in London.

Can I pick your collective brains on this subject? We built our house in 2000 before I learned about Peak Oil. We we did try to make it efficient, but didn't have the budget for really-forward-thinking plumbing/heating and electrics. As a result, we have a conventional, well insulated house, with a sealed gas central heating system (no tanks in the loft), running off a Vaillant gas condensing boiler and traditional wall-mounted radiators. We cook off gas.
How easy/difficult would it be to now fit the solar hot water panels or wood burning stove with back boiler mentioned earlier in this thread when the whole system is under mains pressure? Even though this sort of boiler should be commonplace by now, we still get maintenance engineers visiting who are very unfamiliar it and so I'm a bit wary of seeking advice from a name plucked out of Yellow Pages...

Jules

skeptik wrote: What are these people actually DOING out in the middle of the New Mexico desert? Where's the village hall? wheres the local shops, agriculture, industry.

This is not a sustainable community. Its a burb built out of recycled bits and pieces with lots of solar panels. Are they going to build their own cars too?

What do they do when they get a toothache? Get in the car and head for civilisation of course. A useful demonstation of low tech possibilities (and some high tech), but no lifestyle shift. Its still just a New Age Levittown.

You are confusing two issues. The principle of using thermal inertia is one issue and location is a completely different issue. The reason they build in weird places is because of planning permissions..!

skeptik wrote:http://www.earthshipbiotecture.com/Phoe ... xpage.html
Hmm... an interior made of mud and old bottles isnt quite my style.

3 bed 2 bathroom and ONLY a million dollars? SLightly out of my price bracket. Apart from which I dont think Id be able to get planning permssion for one of those where I live, thats if I could even find a plot big enough...

DO they do a high rise version for cities? Up to the 7 floor recommended maximum for post peak oil buildings?

Would BedZed do? Same principle of thermal inertia but in a different costume. I belive we even have a member living there...

MacG wrote: Would BedZed do? Same principle of thermal inertia but in a different costume. I belive we even have a member living there...

That looks pretty good compared to what the yanks are up to out in the middle of nowhere.. Integrated housing and light industrial / workshops. Did they remember to incorporate the shops? How long does it take on foot to buy a pint of milk, a packet of Hobnobs, the Observer and 20 Bensons? or get a load done at a washateria?

Do we have any feedback from whoever is living there? Do the systems work? Are they reliable?

How easy/difficult would it be to now fit the solar hot water panels or wood burning stove with back boiler mentioned earlier in this thread when the whole system is under mains pressure? Even though this sort of boiler should be commonplace by now, we still get maintenance engineers visiting who are very unfamiliar it and so I'm a bit wary of seeking advice from a name plucked out of Yellow Pages...

Hi Joules,

I had a gas combi in a closed system. To convert to wood stove with back boiler I had to have an open vented system installed, with a cold water tank in the loft and an additional expansion tank.

I have a dual-coil cylinder with the wood stove connected to the top coil and a solar hot water panel to the bottom. The system works really well, but all told cost me over ?5000 to convert (not that much I suppose in the grand scheme of things)

Thanks Andy and Bozzio. Bozzio's thermal store suggestion sounds particularly good for my circumstances and is such excellent information that I think you should post it on this thread (it came to me in a private message exchange). I had no idea that these options were open to us. I'll let you know how I get on...

Joules wrote:Thanks Andy and Bozzio. Bozzio's thermal store suggestion sounds particularly good for my circumstances and is such excellent information that I think you should post it on this thread (it came to me in a private message exchange)

This is what I posted to Joules. Hope it helps anyone else with similar questions.



Hi Joules,

Andy Hunt has sent a good reply to your message today about how he uses a twin coiled hot water cylinder connected to a wood fired back boiler and a solar panel. Essentially this is what you will have to do although there are variations to his set up which depend on how much space you have to accommodate fitting a new cylinder and how big your house is /demand requirements.

The bottom line is that it is not hard to convert your system and still retain the plumbing you already have in place. You will need to add the following of course,

- a hot water cylinder of a design which can accommodate several heat producing appliances.
- a solar panel on a south east/south/south west facing roof or wall.
- a multi-fuel stove with back boiler (multi-fuel options are better than just wood burning options as wood may not always be available).

Andy (as I understand it from his description), has opted for a traditional gravity fed hot water cylinder, but one with two coils ready for direct connection to the stove and the solar panel. He has had to install a cold water tank in the loft to feed the cylinder. He mentions he has a gas boiler as well although he's either discarded this altogether or it only heats his radiators.

My preferred option is to install a thermal store which is a traditional cylinder in reverse. In a traditonal design the stored water in the cylinder is heated via a coil connected to a boiler. In a thermal store, the coil contains the cold incoming water from the water main and is heated instantly by the stored water in the cylinder (which is heated directly by the boiler). For a better explanation please visit www.albion-online.co.uk , click on 'solar & multi-fuel' and view the different examples.
Thermal stores work very well with multi-fuel stoves because they even out the temperature fluctuations you get and they retain their heat well due to the large volume of stored water they contain. Their use also means you have mains pressure hot water (good for showers etc) and you save the cost/space of fitting a cold water storage tank. They can be sited in the loft if you are limited on space. You can order them with as many coils as you like so that you can fit (as you will see with some of the examples on the website above) solar panels, conventional boilers and multi-fuel stoves. In your case you will connect the multi-fuel stove to the main tappings (see figure 4 on the Albion site) such that the stove heats the stored water directly, the gas boiler will connect to one coil, the solar panel to another coil and your incoming water main to the domestic hot water coil. In this way your current system remains sealed and pressurised. Your solar panel can then be either sealed or an open circuit such as used by Solartwin, who I fit for ( www.solartwin.com ). By the way, if you have a combination boiler, you can retain your boiler but just disconnect the cold feed to it using the flow and return circuit only. If you have an 'unvented' cylinder then this will need to be changed.

A typical solar panel installed will cost ?3000 after any grant (?400 in England). A thermal store will cost about ?500 to buy. A stove plus back boiler will cost about ?500 (+/- ?200) and depending on whether you have a suitable chimney could cost anywhere between ?250-?750 to fit. Connecting the stove and all other pipe work to the cylinder will probably cost another ?500 -?1250 depending on construction/pipe routes/problems.

Hope this helps. Feel free to ask any more questions.