Another ashp/electricity usage question

[andyscotland]

2 hours ago, TonyT said:

If you are on a cheaper night time tariff, it will be most cost effective compared to gas, particularly if you can heat during the cheap time period

 

Given the COP drops as temperature does (I think?) and at the moment it's a lot colder overnight, I'm curious about where the balance point for this is.

[andyscotland]

4 minutes ago, Roger440 said:

Oil prices are at an all time high, and its STILL cheaper than the alternative, electricity. 

 

Unless you see electricity coming down substantially? 

 

All the signals are that oil and gas will become more expensive over time as carbon and consumption taxes move towards fossil fuels. Meanwhile electricity is expected to come down (or at least, go up less) both due to those taxes changing and also the increasing proportion of renewables generation. Bear in mind at the moment a big chunk of the electricity price is due to the oil and gas price so they will (in theory at least) fall together.

 

The other factor is that you can self-generate electricity - perhaps not enough for winter, but enough to cover e.g. hot water outside the heating season - but you cannot produce your own oil.

[ProDave]

12 minutes ago, Roger440 said:

Oil prices are at an all time high, and its STILL cheaper than the alternative, electricity. 

No they are not.  It was over £1 earlier in the year, even ignoring the silly panic peak in March.

[Roger440]

11 minutes ago, ProDave said:

No they are not.  It was over £1 earlier in the year, even ignoring the silly panic peak in March.

 

Ok, we are below the silly peak. But it was shortlived. But still double what we were traditionally paying.

[Roger440]

20 minutes ago, andyscotland said:

 

All the signals are that oil and gas will become more expensive over time as carbon and consumption taxes move towards fossil fuels. Meanwhile electricity is expected to come down (or at least, go up less) both due to those taxes changing and also the increasing proportion of renewables generation. Bear in mind at the moment a big chunk of the electricity price is due to the oil and gas price so they will (in theory at least) fall together.

 

The other factor is that you can self-generate electricity - perhaps not enough for winter, but enough to cover e.g. hot water outside the heating season - but you cannot produce your own oil.

 

Do you really believe electricity will come down by an appreciable amount? And as you say yourself, they will do together. Contradicting your first point.

 

Also, bear in mind that im viewing this from an angle where i know that i cannot achieve insulation and air tightness levels that are achieved on a new build. So my heat demand will still be higher than new build levels.  So not ideal for a heat pump potentially.

 

Regarding self generation, thats not remotely viable for an electic based heating system in winter. You are almost totally reliant on the grid unles you can build a ful scale solar farm. And at the mercy of blackouts which, inevitably, are coming. Oil gives you a good level of independance. If we cant get oil, then we will have much bigger problems than heating to worry about.

[SteamyTea]

36 minutes ago, Roger440 said:

Oil prices are at an all time high

Well except for all the other times it has been higher.

https://www.macrotrends.net/1369/crude-oil-price-history-chart

 

While direct, universal, support will vanish, probably in April 2023, the Treasury can do a lot to the retail price.

Reducing the environmental taxes is on area, they could shift these to gas, oil, coal, biomass.

 

I think the real problem is that we have got very used to low taxation on domestic fuel, this has kept the price low, and discouraged most investment in energy saving.  This has to change.  It should be up to home owners to sort themselves out, not constant hand outs from the tax payer.  That just adds another layer of bureaucratic 'waste' into the mix.

 

While we will always here the horror stories of children living in damp houses and old people dying under blankets, they are the non typical stories.

We don't hear about the millions of families that have decided to not renew the car this year, or take a cheaper holiday, or just buy less 'stuff'.  That would be boring, and just highlight normal life, and where is the fun in that.

 

You could always buy a couple of those diesel/kerosene hot air blowers as a temporary measure.  Should be easy to get 10 kW of air heating into a building for less than £300.

[Roger440]

8 minutes ago, SteamyTea said:

Well except for all the other times it has been higher.

https://www.macrotrends.net/1369/crude-oil-price-history-chart

 

While direct, universal, support will vanish, probably in April 2023, the Treasury can do a lot to the retail price.

Reducing the environmental taxes is on area, they could shift these to gas, oil, coal, biomass.

 

I think the real problem is that we have got very used to low taxation on domestic fuel, this has kept the price low, and discouraged most investment in energy saving.  This has to change.  It should be up to home owners to sort themselves out, not constant hand outs from the tax payer.  That just adds another layer of bureaucratic 'waste' into the mix.

 

While we will always here the horror stories of children living in damp houses and old people dying under blankets, they are the non typical stories.

We don't hear about the millions of families that have decided to not renew the car this year, or take a cheaper holiday, or just buy less 'stuff'.  That would be boring, and just highlight normal life, and where is the fun in that.

 

You could always buy a couple of those diesel/kerosene hot air blowers as a temporary measure.  Should be easy to get 10 kW of air heating into a building for less than £300.

 

I was only talking about heating oil. Rather than crude.

 

I did ask in my other post what you would do, if having to make a decision now, and having to live/fund it for the next 25 years.

 

They can, as you say, shuffle the taxes around. But will they, and to what extent? And when. Nobody knows. Which makes it rather hard for said homeowners to "sort themselves out". I willing accept i need to do so, but some clear idea of whats coming would be useful.  Policy changes daily, and some of it, we know isnt going to happen.

 

But a decision still needs making. At the moment, ASHP is making no sense whatsoever, especially, as i posted above, not being able to get to current levels of insulation and air tightness on a refurb. Short of knocking it down.

 

My loose plan, subject to daily change, is, keep the oil boiler, fit a massive tank, connect my solar too it too, and get a log gasification boiler for good measure (plenty of cheap wood round here) . If electricity suddenly becomes cost effective, i can easily tack that on. But the cost just to purchase and install probably means that wont make sense for a long time.

[ReedRichards]

1 hour ago, Roger440 said:

What to do?

You design the inside of your house for a heating water flow temperature of as low as you can manage and 50 C at maximum.  You get a large capacity hot water cylinder that can be kept at 50 C or less and with a large enough coil that it can be quickly brought to temperature with water at 55 C.  You install a buffer tank with 28 mm pipes between this tank and your heat source.  Internally you don't use microbore pipes.  You opt for an external heat source.

 

Do all that and (I think) you have hedged your bets by getting a system that is compatible with a heat pump or an external oil boiler.  You would need an oil boiler that is capable of low output water temperatures or it would short-cycle.

[Ralph]

1 hour ago, Roger440 said:

Yes, but you have reduced the heat demand. If your reduced demand house had the same gas boiler as your flat, guess what, it would cost less. 

 

Drives me bonkers when you keep reading that the ASHP is more efficent, but you need to insulate properly first. Insulating is always a good idea. That how you reduce the heat load. It will be cheaper to heat than a poorly insulated house, regardless of the heat source.

Yes that's my point, it's about the house not the heating system. When were installing ours I heard from quite a few doom mongers that we would be ripping it out in 12 months because there seemed to be quite few installations locally where ASHP was stuck in old house without the required insulation. 

[SteamyTea]

25 minutes ago, Roger440 said:

get a log gasification boiler for good measure (plenty of cheap wood round here)

How cheap is that timber?

Quick look on eBay

https://www.ebay.co.uk/itm/394232733783

Work out at about 29p/kWh before it is put into an inefficient combustion chamber.

[Roger440]

1 hour ago, SteamyTea said:

How cheap is that timber?

Quick look on eBay

https://www.ebay.co.uk/itm/394232733783

Work out at about 29p/kWh before it is put into an inefficient combustion chamber.

 

Works out at 4p kwh. In a gasification boiler. Not some hopeless woodburner in the living room.

 

But that is a full lorry load of roundwood straight off the forest floor. It still needs cutting, stacking and drying. So its only 4p if you exclude the labour element. Which is why im ignoring it for costing purposes.

[SteamyTea]

1 hour ago, Roger440 said:

Works out at 4p kwh. In a gasification boiler. Not some hopeless woodburner in the living room.

How so.

There is around 4.5 kWh/kg in timber with 20% moisture content.

 

20 kg x 4.5 kWh = 90 kWh

 

£26 / 90 kWh = 0.288 £/kWh

 

Gasification will not recover all the available energy, or it would be magic.

 

Edited December 14, 2022 by SteamyTea

[Roger440]

24 minutes ago, SteamyTea said:

How so.

There is around 4.5 kWh/kg in timber with 20% moisture content.

 

20 kg x 4.5 kWh = 90 kWh

 

£26 / 90 kWh = 0.288 £/kWh

 

Gasification will not recover all the available energy, or it would be magic.

 

 

You lost me. Are you working that out on your price? I worked mine out of the raw timber price. Not your ebay price.

 

Clearly it wont recover all the energy. Just more than a woodburner in the living room

[SteamyTea]

10 minutes ago, Roger440 said:

worked mine out of the raw timber price. Not your ebay price.

What was your price per kg?

 

[Roger440]

Id need to dig it out. You buy it by the cube. As its can be very wet. Min delivery was a full artic load. And its not got to come far. So haulage was minimal.

 

I worked it out a few times. Then found a website that told me much the same. I was amazed.

 

But you have to "process" it yourself. Which of course is where the cost comes if you were to sell it commercially as dried timber. Ive not included, fuel for chainshaw, new chains etc.

 

If you bought logs, rather than roundwood,  it was,  in round numbers twice as much.

Edited December 14, 2022 by Roger440

[SteamyTea]

13 minutes ago, Roger440 said:

You buy it by the cube

Yes, it is an odd way to buy energy, especially as part of that cube is air.

 

14 minutes ago, Roger440 said:

can be very wet

So paying for water, North Sea gas is pretty dry once delivered. Why is wood wet.

[Roger440]

7 minutes ago, SteamyTea said:

Yes, it is an odd way to buy energy, especially as part of that cube is air.

 

So paying for water, North Sea gas is pretty dry once delivered. Why is wood wet.

 

Thats just how you buy raw timber. I dont make the rules, the forestry industry does. I believe the correct term is a "cord" of timber.

 

It will be "wet" because it just got cut down the day before.

[Roger440]

Im not sure this is helping the OP much though

 

[SteamyTea]

7 minutes ago, Roger440 said:

Thats just how you buy raw timber

Yes, we used to buy timber to make the saunas like that, but at least it was in planks.

Though thinking about it, it may have been the size of the woodpile before machining, then the lads chopped it up wrong and burnt the evidence.

 

I think energy should be sold by the megajoule, no arguement about how much energy is in it then.

Barmy that we buy it by the volume, mass, or archaic units, and even mixed units, that have their origins lost in history and folklore.

Edited December 14, 2022 by SteamyTea

[Roger440]

19 minutes ago, SteamyTea said:

Yes, we used to buy timber to make the saunas like that, but at least it was in planks.

Though thinking about it, it may have been the size of the woodpile before machining, then the lads chopped it up wrong and burnt the evidence.

 

I think energy should be sold by the megajoule, no arguement about how much energy is in it then.

Barmy that we buy it by the volume, mass, or archaic units, and even mixed units, that have their origins lost in history and folklore.

 

But you are not buying energy. You are buying wood.

 

A lot of it ends up as fence posts. For example.

[SteamyTea]

1 minute ago, Roger440 said:

But you are not buying energy. You are buying wood

Was a general point about the energy market.

Imagine trying to buy transport fuel by the 'enough to get me to London'.

 

[andyscotland]

6 hours ago, Roger440 said:

Do you really believe electricity will come down by an appreciable amount? And as you say yourself, they will do together. Contradicting your first point.

 

Well I made three related points.

 

First, that if at some point the oil price drops from current highs then the electricity price will also drop because at the moment the high electricity price is primarily driven by oil/gas.

 

Second, that regardless of what the oil/gas price does there is an ongoing move to a) decouple the price of electricity so renewables generators are not paid a price based on the cost of the oil/gas they don't use, b) increase the proportion of renewables in generation.

 

Third, that it's pretty likely that as that happens, things like "green levies" etc will gradually be shifted from electricity to fossil fuels - because it makes little sense to put "sin taxes" on the cleaner energy source.

 

All those three factors mean that whatever electricity drops by it's virtually certain that will be more than any drop in the oil price. There is no realistic scenario I can see where oil goes down from current levels but electricity stays the same or goes up.

 

As to whether it will actually drop an appreciable amount, I don't know. It may be it holds around the current level and the oil price goes up higher (especially as carbon taxes are ramped up).

 

6 hours ago, Roger440 said:

 

Also, bear in mind that im viewing this from an angle where i know that i cannot achieve insulation and air tightness levels that are achieved on a new build. So my heat demand will still be higher than new build levels.  So not ideal for a heat pump potentially.

 

I hadn't realised that. All the same I think there's a strong chance that the relative prices for different energy sources will change significantly within the lifetime of the heating system.

 

I suspect the way to go at very least is to invest in getting the insulation and airtightness as good as you can reasonably manage, and designing plumbing/radiators etc to be able to cope with a change of heat source in the future.

 

6 hours ago, Roger440 said:

Regarding self generation, thats not remotely viable for an electic based heating system in winter. You are almost totally reliant on the grid unles you can build a ful scale solar farm. And at the mercy of blackouts which, inevitably, are coming. Oil gives you a good level of independance. If we cant get oil, then we will have much bigger problems than heating to worry about.

 

Well yes, I said that you'd probably not be able to generate enough in winter. But if you can cover hot water year-round and contribute to the heating in the shoulder months that may offset slightly higher costs on the darkest coldest days. Probably depends partly on your actual heat demand - 1 person kicking around a giant house might be more of an issue than a big family taking long showers all year round.

[Roger440]

22 minutes ago, andyscotland said:

 

Well I made three related points.

 

First, that if at some point the oil price drops from current highs then the electricity price will also drop because at the moment the high electricity price is primarily driven by oil/gas.

 

Second, that regardless of what the oil/gas price does there is an ongoing move to a) decouple the price of electricity so renewables generators are not paid a price based on the cost of the oil/gas they don't use, b) increase the proportion of renewables in generation.

 

Third, that it's pretty likely that as that happens, things like "green levies" etc will gradually be shifted from electricity to fossil fuels - because it makes little sense to put "sin taxes" on the cleaner energy source.

 

All those three factors mean that whatever electricity drops by it's virtually certain that will be more than any drop in the oil price. There is no realistic scenario I can see where oil goes down from current levels but electricity stays the same or goes up.

 

As to whether it will actually drop an appreciable amount, I don't know. It may be it holds around the current level and the oil price goes up higher (especially as carbon taxes are ramped up).

 

 

I hadn't realised that. All the same I think there's a strong chance that the relative prices for different energy sources will change significantly within the lifetime of the heating system.

 

I suspect the way to go at very least is to invest in getting the insulation and airtightness as good as you can reasonably manage, and designing plumbing/radiators etc to be able to cope with a change of heat source in the future.

 

 

Well yes, I said that you'd probably not be able to generate enough in winter. But if you can cover hot water year-round and contribute to the heating in the shoulder months that may offset slightly higher costs on the darkest coldest days. Probably depends partly on your actual heat demand - 1 person kicking around a giant house might be more of an issue than a big family taking long showers all year round.

 

You mention moves to decouple the electricity price. Where have you seen these moves? I see nothing of the sort. Probably because too many people making mad money from it at our expense. The government could have done that early on instead of spraying cash about. Genuinely interested in your source of info for that. 

 

I agree, insulation and air tightness is a no brainer. However, for the part of the house with solid walls, overdoing it on insulation is likely to cause a bunch of other issues by moving the dew point closer to the inside of the wall. Hence my comment about there being limits to what can be achieved.

 

As you also observe, things will change during the liftime of the heating system, which is what makes it so hard to choose. If you choose one system, such as ASHP, you are committed. Hence my "multi input" approach that im considering. Which on the face of it is a bunch of upfront costs, but by doing all the installation myself, i can, hopefully keep it sensible.

 

I do have the possibility of some hydro, but ive not yet got round to checking how much head of water ive actually got. Rough guess it will be sub 500w, albeit thats continuous all winter. As always, the upfront cost, even doing it myself, is such that payback is a million years. Which is such a shame as hydro is the ultimate clean power. You can get energy from it over and over again. I can use it, then the same water can be used by the next guy downstream. Shame they make it so hard to do.

 

Oh, and ive got 5 acres, so GSHP could be done too. So many choices..................

[SteamyTea]

2 minutes ago, Roger440 said:

You mention moves to decouple the electricity price. Where have you seen these moves?

Contract for Difference is how it is done these days.  Basically fixed price, fixed delivery, and heavy fines for non delivery.  Offshore wind is now about £33/MWh.  Third of the price of new nuclear.  Cheaper tan gas generation, even before Putin's shenanigans. 

Been going a few years, since 2015 I think, but there are still legacy systems (think the old FiTs as a comparison).

 

No government is going to allow a large percentage of the population to be disconnected because of domestic energy prices, they will want to keep it at about the historical norm of 5% of household income.

Now I think household income is about £38,000, so about £2000 a year spent on energy.  Probably not that far off that with these prices.

You have to remember that the price was artificially driven down by a few (about 30) companies that had dreadful business plans.  We are now paying the price, in part, for this.  I think Bulb, just one supplier, is running up a few £bn in government debt, it could not even be given away.  Octopus has recently taken over the customer list , but I suspect it will be a separate company as the deal is that, after a few year, if any money is made from Bulb customers, Octopus will give the treasury a few shillings.  Some people greed, to save a few pence, has cost us all about £160 this year so far.

[Thedreamer]

2 hours ago, Roger440 said:

 

You mention moves to decouple the electricity price. Where have you seen these moves? I see nothing of the sort. Probably because too many people making mad money from it at our expense. The government could have done that early on instead of spraying cash about. Genuinely interested in your source of info for that. 

 

I agree, insulation and air tightness is a no brainer. However, for the part of the house with solid walls, overdoing it on insulation is likely to cause a bunch of other issues by moving the dew point closer to the inside of the wall. Hence my comment about there being limits to what can be achieved.

 

As you also observe, things will change during the liftime of the heating system, which is what makes it so hard to choose. If you choose one system, such as ASHP, you are committed. Hence my "multi input" approach that im considering. Which on the face of it is a bunch of upfront costs, but by doing all the installation myself, i can, hopefully keep it sensible.

 

I do have the possibility of some hydro, but ive not yet got round to checking how much head of water ive actually got. Rough guess it will be sub 500w, albeit thats continuous all winter. As always, the upfront cost, even doing it myself, is such that payback is a million years. Which is such a shame as hydro is the ultimate clean power. You can get energy from it over and over again. I can use it, then the same water can be used by the next guy downstream. Shame they make it so hard to do.

 

Oh, and ive got 5 acres, so GSHP could be done too. So many choices..................

 

I've adopted a multi input approach. Use an exhaust air source heat pump for my domestic water and a wood stove for my heating. 

 

I have never been convinced by large external air source heat pumps, for the average family they are expensive to install and run. Worst of all they become less efficient when you need them most.