Where to start with shift from oil to alternative around the house?

I'd really appreciate if someone could point me to some answers/a group/site/forum or even give some answers here to the following. I've already spoken at length the EST and Low Carbon Homes people. Here's what we (a couple) have, and have found.

We bought a small chapel which has been renovated some time ago. The roof has very little insulation, but has a tiny loftspace with big overhang, ie, nowhere to get much loft insulation. Sempatap has been recommended by EST, but there's no grant for that.

The walls cannot be cavity as they are the original.

The cooker is an old Nobel (like an Aga) which is oil fired, uncontrollable, on all the time, and heats the kitchen, tank of hot water, and one radiator. Oddly, seeing as so much is wasted heating hot water anyway, they had an electric shower! But I think this is to do with water pressure as it's tank water (no mains). However I'm sure mixing pump technology has come on since then?

There's an LPG boiler which ONLY does the CH rads, but it looks like there were plans to get it to run the DHWC primary too.

Again, it seems there's no grant for any of the above any more (so much for govt energy policy!).

Onto the future: I think the Nobel/Aga thing has to go, I'm sure it was great when oil was 9p litre, but I have no plans to get another oil delivery! But LPG tank gas is even more expensive; however at least the boiler can be controlled, and if we swapped the Nobel for an LPG cooker, that would help. Unless someone out there is making a compatible used chip fat equivalent of standard home heating oil cheaper?!

So, let's assume we get rid of the Nobel. Then we need to heat water. As the roof needs to be done at some point, I was thinking of solar, but along the lines of buying my own =A3800 evacuated tube panels and get a qualified plumber to install it, rather than pay some ripoff solar company =A36000 for the same.

Solar thermal is the green thing I'm going to do - I know some will disagree, but I've done the sums, and it's the only thing which works, and it needs to. I'm steering well clear of solar PV, wind, and wood- chip boilers seem not only expensive and unreliable, but the chips are rising fast in price, and are expensive to get delivered, and even a modest boiler burns a lot of woodchips.

I initially thought no to ground source as the garden is small, but air-source sounds interesting for winter heating. I need to dig up the kitchen and bathroom floors anyway, so maybe air-source > underfloor might replace what the Nobel gave off? The only thing with that, is that electricity supply is flaky round here.

The other thought is to replace the current efficient fairly new Clearview wood burner with a water heating equivalent, and use a thermal store. As I understand it, I can input wood stove, solar, air/ ground source, gas and/or economy 7 electricity, and then the system which needs it just takes it off via its own heat exchanger. I know that sounds expensive, but it does allow diversity of supply.

The reason I'm asking here is that all companies seem pushy on expensive impractical stuff - I want an engineer not a salesman. And a lot of forums I find just descend into people arguing about climate change. I'd just like to stick to practicalities! And publications like Green Bible are just full of adverts for the energy equivalent of homeopathy, and the more solid books are out of date with prices.

So, any pointers greatly appreciated!

Reply to
lardconcepts
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You say "no cavity" but that doesn't mean you can't dramatically reuce the heat loss. If the walls are 220mm thick brick then they lose about 2 W/K/m2 I think. Putting 100mm celotex on the inside would reduce this to 0.3 IIRC.

Robert

Reply to
RobertL

1)Insulation will get you the fastest payback rate. 2)Consider solar as preheater for whatever DHW system you use. 3)Is your daytime electricity demand likely to be lowish? if so then use eco 7 nightime power to run air/ground source heatpump to heat a BIG* (possibly underground) thermal store to about 50 degrees. Use this for UFH and possibly an alternative for the solar preheat when there is minimal sun. I think nighttime elec is about half the STANDARD tariff and the heat pump will get you around 3x the energy you are paying for. But the daytime Eco 7 power is very expensive so you need to check a power budget. 4)Bottled gas cooking is pretty low cost and gas hob tends to be the cooks favourite.

  • The favourite source for big storage vessels used to be stainless steel brewing vessels buried underground with loads of foam insulation. I've not looked at these for a while.

How's this to start with?

Bob

Reply to
Bob Minchin

I would say that just about every fashionable thing you seem to want to=20 do here, is in fact completely wrong.

If you cant insulate, and want to be green, don't heat at all.

Oil is cheaper than LPG gas or electricity, so stay with oil.

If you don't like Agas you wont like wood burning stoves.

Solar heating is a waste of money.

In fact, you have bought the wrong property. I think you want a cheap=20 taylor wipeout hutch on a modern estate...

Reply to
The Natural Philosopher

The cheapest heat source is mains gas, the next cheapest is oil. Price rises havent changed that. So maybe look at a controllable oil burner, assuming the existing Nobel cant be made controllable in some way.

Solar hot water is hard to get it to pay its way. Not impossible, most most systems never do. Solar warm air OTOH gives much better payback if properly designed.

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you want to go with solar hot water, you can optimise payback with a large system by using different types of solar heater for each stage of water heating. As an example...

  1. Tarmac heater to prewarm cold water at the bottom of the cylinder
  2. Flat panel to then raise the next layer up of water in the HW cylinder to warm.
  3. Vac tubes to get the next layer up of water piping hot, and warm- hot in winter.
  4. Oil fired heat to top off the top of the tank, ensuring fully hot water at all times.

Its only worth doing that with a large system, not just a cylinder feeding taps and shower.

NT

Reply to
meow2222

Sadly you have summed up the situation with regards professional help quite nicely here.

There are a large number of people looking for answers and the Snake Oil Factory is churning out the *answers* at full gallop. What they miss, the Ecobollox Warrior covers.

Perhaps the Wiki could have a section outlining the simple ways to get real and informed help in this sort of matter?

Not everyone is fortunate enough to have access to a group like this.

Reply to
EricP

what help sources do you have in mind? So far there are links to here and alt.solar-thermal, and a couple of aricles on solar.

NT

Reply to
meow2222

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember Bob Minchin saying something like:

Or bulk milk tanks from defunct dairy farms. Dirt cheap.

Reply to
Grimly Curmudgeon

Brilliant! Some good ideas there I'd not thought of.

Although sound ideas, if they're to be put UNDER the house, aren't we talk> Solar heating is a waste of money.

Depends if you believe the grossly inaccurate RICS figures or look at people who've been ripped off for =A39000 for a 2-panel system, or people who've fitted their own for under =A31k and are seeing paybacks <

5 years.

Nice phrase, but not true :) Every pr> Solar hot water is hard to get it to pay its way. Not impossible, most

Wanted to thank you not just for the ideas, but also for drawing my attention to the UK DIY FAQ/WIKI which I didn't know about. Don't know how I missed that in my Googling...

Gosh, you lot are knowledgeable! I instantly dismissed the Nobel conversion from wick to controlled burner as I'd been told it was impossible, but I might go and have another look at that. It's just the idea of it burning all summer at =A320/week that fills me with horror - in my last house, that was my total energy bill PER MONTH! (no-one believes me,but the meter doesn't lie - unless it was dodgy but I wasn't complaining!)

Again, thanks for all ideas so far.

Reply to
lardconcepts

I've not heard of a wick based central heating oil boiler before, sounds primitive. No chance of adding a pilot flame and a valve to control the main oil feed?

NT

Reply to
meow2222

I think it might be possible, judging by these sites (which explain more about wicks too)

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the second one is just so head-ache inducingly badly made I keep losing the will to get to the part where they actually say what it is they do!

Ho hum. I'll let y'all know what I find about that! At lunchtime, again someone said about converting it to solid fuel (wood). Still not convinced.

Reply to
lardconcepts

Just to update my own post on this.. since posting here originally, I keep hearing people on tv, radio and in the paper talking about this book called Sustainable Energy - Without the Hot Air.

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in case anyone thinks I'm trying to get associate referrals, well firstly, there's no associate link, secondly, you can download the whole thing for free!
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)

Only skimmed a few chapters, but I love that fact that it not only shows the working and quotes the sources but best of all it doesn't draw any conclusions or argue for or against any particular method.

I'm already changing my mind on a few ideas for the house...

Has anyone else read this? What do you think? I'm also considering an induction hob - are the figures really as impressive as they look? They're falling in price, might be affordable soon.

Reply to
lardconcepts

In article , lardconcepts scribeth thus

Theres more sense in that book that all the greenwash thats doing the rounds;!...

Reply to
tony sayer

I helped him get his publishing deal.

Reply to
The Natural Philosopher

On Sun, 24 May 2009 02:44:23 -0700 (PDT) someone who may be lardconcepts wrote this:-

As I recall, in original form it suffered from a number of fallacies, one of which was that electricity demand would grow at a steady rate, presumably due to some immutable law of nature. The same used to be claimed of motor traffic. I noted recently that he has dropped that assumption, which is good. However, given this early howler I'm not too bothered to look at it again and see how much better his analysis has become.

With the official opening of the Whitelee wind farm by the First Minister [1] I did have occasion to do some quick and dirty calculations to compare the future expanded 452MW Whitelee with some other generators in Scotland. Longannet, the second largest coal fired power station in the UK (and third largest in Europe, according to Wikipedia [2]) and Torness/Hunterston B were the comparisons I used.

I used annual homes equivalent as the comparison, the method is standard across all forms of generation and outlined by the BWEA [3].

Number of households = installed capacity (kW) x capacity factor x

8760 / 4700. Where 8760 is the number of hours in a year and 4700 the average house kWh figure [4].

Capacity factors are from Graham Sinden [5]. For these purposes the important sentence of that letter is, "Different types of generators operate at a range of capacity factors - during 2004, gas power stations had a capacity factor of around 60 per cent, nuclear 71 per cent, hydro 37 per cent, pumped hydro 10 per cent, and coal 62 per cent."

The figure for Whitelee is actually 252,735 houses, the newspaper/spin doctors rounded it down to 250,000, assuming a capacity factor of 0.3 which is about the UK average.

452,000 * 0.3 * 8760 / 4700

Now coal. Longannet is usually stated to be a 2400MW station, for example [2], but Scottish Power have only fitted acid rain reduction equipment to three of the four units and propose to do the same with the additional acid rain reduction equipment they are currently applying for permission to fit. So it is more realistic to consider it as a 1800MW station with an extra 600MW for emergency use, which is the line Scottish Power are taking in their documentation for the additional equipment. Using a capacity factor of 0.62, that 1800MW of capacity will supply 2,080,034 houses in a year.

That means that a little over eight Whitelees would be needed to equal one Longannet. 2,080,034 / 252,735 If all four units were fitted with acid rain (and carbon capture) equipment, as I would prefer, then eleven Whitelees would be equivalent to one Longannet.

Now nuclear. Torness and Hunterston B are rated at a total of 2090MW at the moment, according to the British Energy web site [6]. That gives a figure of 2,765,737 houses a year. In other words just under eleven Whitelees are equivalent to current nuclear output in Scotland.

The calculations could be improved by using site specific figures, but using generic figures is enough to get a feel for the numbers. Eleven Whitelees are something Scotland could accommodate, the politicians just need to ensure we get on with the job not the least by resolving planning and connection delays. It would probably not mean eleven Whitelee sized wind farms, one Whitelee and 20 half the size may be more likely.

About half the hydro sites the NoSHEB identified were built, so there is plenty of room to expand that. There is also wave and tidal generation which are coming along and have massive potential.

[1] [2] [3] [4] I have seen figures of around 3300kWh in some sources, it doesn't actually matter for these calculations as it is constant across all forms of generation (I ignore higher levels of electricity saving being part of a high renewables scenario, to avoid accusations of bias). [5] [6] and
Reply to
David Hansen

All very well but what about windless days .. they do have them up there?..

Reply to
tony sayer

Dynamo Dave doesn't understand peak to mean. Only average. Neither does he cost ion te transmission line costs for these windfarts, or the backing up costs.

Dynamo Dave looks at 50 year old nuclear stations, and quotes 70% load average. New sets are 95% or better.

So, the whole of Scotland might produce on average, and occasionally not at all, what Sizewell B does reliably for the size of a small office block tucked away on the coast.

Reply to
The Natural Philosopher

On Sun, 24 May 2009 21:55:43 +0100 someone who may be tony sayer wrote this:-

What about windless days?

Even if there is a day when it windless across the whole of Scotland (very unlikely) the wind farms are connected to an electrical system with other sources of generation. In fact wind is easier to accommodate than coal or nuclear, both of which are prone to sudden and unexpected large failures which leave a large hole in the supply. The wind does not suddenly stop or start blowing across the whole of Scotland and its variations can be predicted well, which is a lot easier to cope with than the sudden failure of Longannet.

Reply to
David Hansen

Don't sweat it, the fact that the 30% load factor for wind farms takes into account windless days seems to have passed 'em by.

The day to day, hour by hour, management is a problem but not a particulary onerous one provided that wind is not a large percentage of the total demand.

Putting the number of wind farms (note farms not individual turbines) into the context of conventional power stations is good. Whitelee has 140 turbines so the 10 or so farms required is another 1400 or so individual turbines. Whitelee covers 28 square miles (7 x 4 miles) so ten times the capacity would require the equivalent of a 70 x 4 mile band of turbines. Or roughly the distance from Swindon to Greater London.

Reply to
Dave Liquorice

Quite common. Research has been done. There's about a 95% chance of two or more calm days (calm enough to invalidate windfarms) across the whole of Northern Europe, let alone Scotland, every year.

Expensiive standby gas powered stuff in Denmark. Which burns more idling away in case the wind drops than it would if the damn things were simply used as generators in the first place.

Not if you have enough of them.

No, they cant.

So build 5 or ten Longannets, or better still, 5 or ten nukes.

Reply to
The Natural Philosopher

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