is heatpumps the only non fossil fuel way to heat your house?

thebourke

is heatpumps the only non fossil fuel way to heat your house?

bullit_dodger

https://www.boards.ie/discussion/2058261118/is-heatpumps-the-only-non-fossil-fuel-way-to-heat-your-house

Depends on what you mean, but electric heaters powered by solar?

(Solar panels unlikely to capture enough energy in winter to heat your house, but technically it's not fossil fuels)

graememk

I think I know what your asking, heating without burning stuff locally.

There's infra red heat panels, and resistive heaters. But they are all 1kwh of electric in and 1kwh of heat out, (more or less)

Heatpumps depending on how hot you make them run, it's 1kwh in of electric in, it moves 2-5 kwh of heat into your house

KCross

https://www.boards.ie/discussion/2058261118/is-heatpumps-the-only-non-fossil-fuel-way-to-heat-your-house

The only other options really are Solar, wind and hydro.

Solar is somewhat limited in winter. Least amount of generation when you need heat the most.

Wind and hydro are very location specific and not cheap.

So heat pump is the best option for the majority.

One thought though, are wood pellet burners considered renewable if the pellets are sourced from renewable suppliers? Maybe that’s an alternative.

Girl Geraldine

Geothermal, if your circumstances allow. But it is very, very expensive. You'd probably be cheaper and better off in the medium term to do a bit of insulation and a good oil boiler.

thebourke

i am looking at getting the external walls insulated.

I have a gas boiler.

House is bult 1960s.

So was wondering what the alternatives are to a gas boiler?

magicbastarder

wood is not a fossil fuel.

jkforde

++1 invest in as much insulation as possible esp. for dormers and tap into any grants (and yes, you\contractor have to duly jump thru SEAIs adjudication hoops but it's just a checklist process and they have their jobs to do at end of day)

but yeah, heat pumps are best option but I've read that they only perform optimally in airtight housing

thebourke

how much does an air pump cost with installation?

KCross

https://www.boards.ie/discussion/comment/119547349#Comment_119547349

Its like asking "how much does a car cost"! 😉

Depends on the size of the house and what work needs to be done and what company is providing the service and which HP you pick and what grants you apply for.

It will likely be a 5 figure sum but you need to get quotes specific to your house.

Ubbquittious

Heatpumps are a fossil fuel way to heat your house given the large portion of electricity generated by gas over here. Not as bad as burning the gas directly but still using fossil fuel.

unkel

I use crypto mining rigs to heat my house. 100% efficient and making a profit*, while giving heat for free.

*at the moment it's making a profit and has done so all of last winter, this was not always the case and will not always be the case. But even when it is making a loss, it will in most cases still be cheaper to heat your house with a mining rig than with gas or oil

Girl Geraldine

https://www.boards.ie/discussion/comment/119547420#Comment_119547420

The thing is, when contractors hear that there are grants involved, they just jack up their prices in step with the grants.

paddylonglegs

On external wraps, what is the average square metre cost people are getting? Or is it job dependent?

magicbastarder

external wraps are suited to certain wall constructions. the cheapest (and least intrusive) seems to be cavity wall injection, if cavity walls (not cavity block) is what was used to build your house.

paddylonglegs

https://www.boards.ie/discussion/comment/119550959#Comment_119550959

Yeah haven’t investigated that far so trying to get gauge of cost for worst case scenario

Thespoofer

Why do the ROI not offer grants to have oil/gas boilers replaced by biomass/pellet boilers as they do in UK/NI ?

Its a renewable source.

unkel

Not really @Thespoofer. If you look into it a bit more, the percentage it is actually renewable is very low. And it is still producing very bad emissions. It's not a solution.

mickdw

For a 1960s house, you will need to go full retrofit to make it suitable for heat pump. That will likely mean up to A2 rating which will in most cases mean floor, wall and roof insulation plus windows and airtightness brought up to spec.

This work using seai one stop shop is absolutely out of hand cost wise as grant amounts just seem to be lumped onto costs to the point of grant not being worth while.

A more reasonable solution is to insulate where possible without too much disruption and run an efficient gas or oil burner.

So go big on attic insulation which is cheap and easy. Pump walls if possible and I would say if you have structural timber ground floor with void, look at insulating and airtightness there too.

The point is that electricity is flexible - what is now gas produced may be wind/solar/fusion produced in the future. The same can't be said of oil or gas ( maybe hydrogen or something else renewable COULD replace it but by no means as easily as electricity)

Was replying to Ubiquitous

unkel

Exactly what @mickdw says. It horrifies me that tax payers money is being made available for deep retrofit. Most of that money will go towards labour costs and profits for the installer. Very little towards actual insulation. We will just have to live with older houses and do the basic insulation that we can for reasonable money. For the rest we will just have to clean up our sources of energy. If we do a good enough job, those older houses can be heated with electricity, but with conventional heating, not heatpumps.

Triapin

So my house was built in the 1980's...triple glazed windows, but room to insulate further. Roughly 130m squared and I am wondering is a heat pump a viable option or would a gas or oil burner be more realistic?

jkforde

if your BER is anything less than A3 (critically air tightness\drafts) I would suggest go with high efficiency oil burner and keep improving insulation and maybe active ventilation (for dampness).

thedart

I would suggest turning down the stat a few degree. Have worked in houses last winter and see stats at 22-23 degree.

17-18 degree, dial down the heat. Examples mentioned are people who have no medical issues or elderly people or any other thing that may need to have a house at that temperature.

mickdw

https://www.boards.ie/discussion/comment/119566853#Comment_119566853

I would suggest it's unlikely that it would be suitable however if it was of a design that made it relatively simple to airtight and insulate, you could look at heat pump but it would need to be relatively airtight. No 1980s houses were anyway airtight.

It's all well and good going for heat pump but if it has to work too hard to heat the house, your electricity bills will absolutely be through the roof. I know of a case where the esb bill was 700 for 2 months when the average house was getting a 2 monthly bill of 250.

Mickeroo

I think there could be potential in these things, though I'm a bit vague on how the tech actually works. Too good to be true?

https://www.youtube.com/watch?v=NOUDbx1tX-A&ab_channel=EverythingElectricShow

bullit_dodger

https://www.boards.ie/discussion/comment/119578125#Comment_119578125

Effectively a sand battery. I like the concept myself, although it only really works if you have access to cheap green tariffs. Heats up the ceramic block internally to 500C or so when the leccie is cheap, and then can release that into the heating system during the day when you call for heat.

Great if you can do that heating at (say) 2am on a smart tariff like octopus - but people on a flat rate 24hr tariff it could be a pricey replacement.

It's got a few draw backs for me. It's large (I couldn't replace my boiler unit in the kitchen with it), it's 375 Kg, so not exactly easy to move about, but super to see these alternative heating systems coming to market. Could be a good alternative to someone who has a house where a HP doesn't work. (Drafty etc)

unkel

It's just like the "storage heaters" popular in Dublin in cheap ass newly built tiny apartments / flats in the 90s 😁

Just heat a block of concrete during cheap night rate hours and the heat will be coming slowly off it for the rest of the day. That is the plan, but in practice this mostly didn't work as by the time the occupants came home from work in the evening, the heaters had gone cold again. Now obviously you can overcome this by better insulation and controlled venting. I didn't watch the video, but I guess that is what that does?

SD_DRACULA

https://sunamp.com/ looks quite promising as you can charge them from PV or grid and they can be connected to water cylinder/gas boiler even but I think for now they are only for heating water.

They are working on a version that can hook up to existing water rads around the house and once that happens it should be a game changer.

They are not massive and if they can do heating/DHW then what's the point of heat pumps? Also quite cheap in comparison

Ubbquittious

https://www.boards.ie/discussion/comment/119578447#Comment_119578447

All that's old is new again!

geotrig

https://www.boards.ie/discussion/comment/119547563#Comment_119547563

Im curious as I've seen you mention this once or twice ,how does it heat your whole house ? you may have explained this already but I haven't seen it ?

unkel

@SD_DRACULA - "if they can do heating/DHW then what's the point of heat pumps?"

These have an efficiency of 100%. Heat pumps can have 300-400%. The latter are the best choice for newly built very well insulated houses. But when it comes to the time to replace gas / oil boilers in older houses, any alternative should be considered as retro-fitting a heat pump is very expensive and the house might not be suited for it without extensive upgrades

Xcellor

https://www.boards.ie/discussion/comment/119578125#Comment_119578125

Interesting, its centralized storage heater which then transfers heat to water so works with existing rads.

No outdoor option though. Ive an old non condensing kerosene boiler that always feels like its about to give up and I'm struggling to see what alternatives are available.

At the moment Im considering just putting money into getting cavity pumped this side of winter and i've already laid an extra 200MM of insulation in the majority of attic.

unkel

One rig in the living room (coldest room of the house), one in the kitchen / conservatory. Leaving doors open this heated the upstairs as well (heat rises). We did have a mild winter though last year

Punchin A Keyboard

At least a ashp in theory is cooling the planet, well depending on its source of juice versus heating a house with mining rigs.

Despite some interest in Blockchain's distributed ledger for documentation validation, I have never been a fan of crypto mining due to the environmental issues. Each kw going into a GPU or worse a cpu off a peaker is a kw that need not have been generated.

That and trying to source any GPU for a gaming rig, am I being hypercritical here.

Hopefully i have not offended too many folks here.

Gretta moment over

graememk

https://www.boards.ie/discussion/comment/119578447#Comment_119578447

More or less, heat up on cheap electric, but it's plumbed into your traditional wet heating loop. And just acts like a boiler. Call for heat and it puts heat into the house.

Looked into it a while back, I think it can charge at 10kw, stores 40kwh of heat.

Storage heaters with a lot more control. I think it could even act as a combi I think.

unkel

@Punchin A Keyboard - "I have never been a fan of crypto mining due to the environmental issues. Each kw going into a GPU or worse a cpu off a peaker is a kw that need not have been generated."

How do you mean? I heat my house with electricity, this is 100% efficient and does not involve me burning fossil fuels. Also in winter, well over 50% of all electricity generated in Ireland at night is from wind. During the summer my mining rigs during the day ran almost 100% on solar PV

And globally, the vast majority of crypto mining is done on renewable energy too. Not because many miners care, but because it's the cheapest form of electricity

blackbox

If the problem with heat pumps is that they only work in an airtight house, it suggests that they have a much lower heat output than a normal boiler?

Why can you not get a heat pump with a decent heat output that can act as a direct replacement?

I understand that they are less efficient at achieving high temperatures but it looks like the savings come from the insulation, not the fuel.

Would it be a better option to insulate your house to heat pump standards, but continue to heat it with a normal boiler?

Punchin A Keyboard

The newest r290 propane ones are meant to work up to 75c so are meant to work with existing rads. I believe CO2 heat pumps go higher but are only used in industrial settings.

I hope to get one myself after some insulation improvements.

Now my concern is flow rates due to 10mm microbore pipes.

And yes updating the insulation to hp standards and running with an existing boiler may be a great option.

graememk

https://www.boards.ie/discussion/comment/119579126#Comment_119579126

In short Yes. Insulate.

if your really looking to nerd out on it, Check out heat geek on youtube, (and urban plumber)

houses dont have to be airtight for heatpumps. They just need to be able to meet the heatloss of the house.

Flow temperature is the big thing with heatpumps (and condensing gas boilers) The lower the flow temperature, the less heat a radiator can put out into a room (hence the need for oversizing radiators)

A lot of condensing gas (and oil) boilers, are often not run at a low enough flow temperature to allow the condensing mode to be activated.

a quick way to see if your house is heat pump ready, is to lower the flow temperature of your boiler until the house isnt getting warm enough.

Gas boilers have often been oversized, which leads to cycling, which is less efficient than a lower powered one running for longer.

Heat pumps, on a running cost perspective vs Oil gets quite interesting. Cheapestoil.ie has a litre of oil at around 1.40 for me at the moment, there is 10 kwh of heat in a litre of oil, and you have a good condensing boiler, 95% efficient , 9.5kwh per litre. 14c per kwh of heat.

If your able to get a COP of 3.5 with a heatpump (considered poor, they are aiming for 4+ now) and your electric rate is 30c(although even that is getting rare now!) thats 8.5c/kwh... say 2000L of oil a year? 19000kwh of heat, 1600ish for electric vs 2800 for oil.

Although my dad was chatting to a friend and they are going through 1000L every 2-3 months, But it is a huge house, and a B&B. so thats part of it.

Punchin A Keyboard

@unkel sorry I am not trying to troll but when I think off all the power being used that could be diverted to other uses or not generated at all.

If there was feasible seasonal electrical storage then I would not have as much as a issue.

Or a Mr Fusion to power your house

Thespoofer

https://www.boards.ie/discussion/comment/119578581#Comment_119578581

Just out of curiosity, did you feel much of a difference with the extra 200mm in the attic ?

unkel

https://www.boards.ie/discussion/comment/119579370#Comment_119579370

Not sure what you mean. I slow down mining in summer as I don't need the heat. I have a very large solar PV setup plus large battery so I generate my own electricity to power my mining rigs (and charge my cars). Where's the issue there?

And in winter I do need the heat. Which I generate with electricity, which is a lot cleaner than from oil or gas as a substantial part of it comes from wind

cruizer101

https://www.boards.ie/discussion/comment/119578447#Comment_119578447

Its the same concept but done much better. I'm not sure about that particular model but some I've seen have vacuum insulation similar to a thermos so the can keep the heat in them for a few days and then heat a loop of water as heat is required by the house so slowly meter it out.

Far better than the dumb storage heaters of old.

I'm still not fully convinced by them being a full replacement for a boiler but in certain situations they do have a lot of potential.

bullit_dodger

https://www.boards.ie/discussion/comment/119578453#Comment_119578453

Well, heat pumps work on a different principle. With those storage heaters, your effectively working the unit like a battery. Store/put the heat into the "battery" when the electricity rate is good (usually during the night like 2am) and then later on in the day, you can heat the water for your radiators from that same energy/heat you put in that morning - not having to use expensive electricity during the day. Course, with this system there will always be some losses. 90% is probably a success, but if you night rate is (for example) 8c/unit and your day rate is maybe 30c, then even 10% losses is fine. Your still coming out ahead.

Heat pumps though work on a compression basis. The effectively heat the inside of your house by "stealing" energy from outside your house. This means that if you put 1Kw into the process, you can get sometimes 3-4Kw back. It sounds too good to be true, but it works well for many houses. Problem is that they typically can't heat the water to much beyond 50C, so you have to have big radiators etc. while the Tepeo's can heat the water to 70-80C meaning you don't have to replace radiators etc.

Xcellor

https://www.boards.ie/discussion/comment/119579810#Comment_119579810

Definitely house holds heat much better. Zero heating on for months now, house never goes below 21 degrees. It's mild but during winter took a lot less to get the house warm. That and fixing window seals and hinges made a big difference.