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Was considering solar thermal, or solar battery, anyone know if you can combine these, or would you still need to keep a hot water tank?
They both require a tank. PV outputs to immersion heater. Solar thermal via a coil.
I meant one of these. Not sure if there's an equivalent that can be 'charged' using solar thermal.
Interesting to see just how little power you need if you can keep the heat in:
Even in winter the TV and two adults lying on a sofa is enough to keep our living room warm without the radiator; warm enough that we end up having to open the door to let heat out. We have a large floor-ceiling window with a thick double curtain on it that goes all the way to the ground. Other than that, it's just a 15 year old bog standard newbuild. It is a semi though.
I am almost all electric now, heat pump, solar panels, induction hob, e bike and car.
Just the campervan burning dead sea creatures.
I also had the issue with small bore heating pipes mentioned by Hagi when installing the heat pump but went ahead. You hardly notice the pipes on the wall so glad that I did.
Solar PV alone to run a heat pump in my opinion. When you want heat there is normally not much Sun.
Are their any remotely viable long term energy storage technologies available? I mean long term as in from the summer to the winter. Thinking about micro generation really rather than grid scale.
Thermal stores and state change batteries are really useful but I don't think you could store enough or for long enough.
I know that efficiency from solar PV is still not great, if you combined it with hydrogen production which is also pretty poor or compressed air or something else is it simply not worth the effort?
Batteries would obviously need to be ridiculously enormous and use far too many resources but would a large pressure vessel be ridiculous too?
Tank your attic. Pump water up in summer. Use it as micro-hydro in winter.
Wife is a property developer, her latest new builds are all electric. A block of 8 flats all using thermaskirts for heating.
First winter using them so will be interesting to see how they perform. As some of the flats are fairly small (1 bed studio) the thermaskirt looks a lot cleaner than having radiators on the wall.
She wanted solar as well, but the weight was an issue.
She’s just bought some new land and these flats will also be all electric, including provisioning of a meter for EV’s.
Not yet, but it's part of our plans in the near future.
House needs some work to enable low temperature heating systems, but we have an extension planned which will help get this done.
Next car will be electric as more s/h options with adequate range become available. I couldn't afford a car that new at the moment.
Are their any remotely viable long term energy storage technologies available?
No. Not for the home or even small scale consumer.
To the OP - about 30% of Scandinavia. That's a guess number, but it's mostly electric for heating, or wood fires on occasion. Gas and coal simply non options. If you have an electric car, there you go.
100% renewable in Norway . 🙂
You can use a GSHP to store energy, to a degree. Best if you have a runway or similar though 😁
A battery would work quite well. V2G is also viable
Not sure if there’s an equivalent that can be ‘charged’ using solar thermal.
That would be a water tank. Which is why solar thermal is so good. Tanks are not bad.
I’ve thought about it too. If it’s so critical to buy an EV, why isn’t it as critical to switch to electric heating and hot water?
Both are critical. You won’t be able to buy a petrol/diesel car or a gas boiler in 20 years time. We’ve shifting too slow on both, but there are genuine reasons why neither can be done quickly. We’re not talking enough about gas central heating.
[ gas boiler and diesel car here ]
Does anyone know if there are heat pumps that can run alongside a gas boiler without a tank (I.e. shared radiators). I'd like a system with a heat pump run by solar when light available but that did not force use of expensive electricity when there was not enough light.
Are their any remotely viable long term energy storage technologies available?
If you had a decent sized garden, wouldn't it be possible to dig a hole, put two water tanks one on top of each other, and build your own pumped water storage system really quite easily?
A couple of days ago I mentioned that I had gone fully electric with an Air Source Heat Pump and EV apart from a diesel campervan. I checked the numbers and they are interesting.
Annual use in 2019/20 was approximately 10,000kWh gas and 2,000 kWh electricity.
Annual use in 2020/21 was approximately 5,500kWh electricity and no gas.
Using the heat pump for space heating has made a significant difference in energy use and carbon footprint though not cost as electricity is more expensive.
I have read unconfirmed reports that environmental levies in the UK will be moved from electricity to gas bills which would change the balance of pricing in favour of electricity if done. This appears to make sense if we wish to reduce use of fossil fuels such as gas.
Still a looooong way to go to match Edukator's <2,000kWh though.
Good man!
Yes, our house is fully electric. Built 5 years ago with an ASHP. Heavily insulated, qith a good spec. Costs around £120pm, and thats for a family of 4. I'm guessing that's going to start creeping up now.
Long term plan is to install solar on the rear as its in direct sun most of the day, and put a storage battery in the garage.
A battery would work quite well. V2G is also viable
Not long term it won't. What's V2G when it's at home?
If you had a decent sized garden, wouldn’t it be possible to dig a hole, put two water tanks one on top of each other, and build your own pumped water storage system really quite easily?
Only if your garden encompassed an entire valley with suitable elevation or had a deep mine underneath it.
Storage is one thing I'm happy to leave to EDF for the moment. Pump storage using reservoirs is cleaner than batteries. The more surplus renewables a country has the better it can use existing reservoirs for pump storage. The Germans are building new ones but understandably mmet opposition. The key will be to put them in places where they can be used for both irrigation and electricity buffering, possibly with recreational use too.
I'd like to be able to use my car for storage. Of the 52kWh I'd be quite happy to use 20kWh to reduce my own demand during peak demand and even allow EDF to take some back.
Storage is always inefficient, cars lose 15-40% depending on the charge rate and so do power walls, better let the big companies do it when necessary than have lots of consumers second guessing.
Agree with Edukator, although I realise the biggest reason for people wanting to store the energy is excess power vs the derisory export tarriffs. Surplus is inevitable if you design your system to be self sufficient through most of the year but it would be nice if the economics stacked up better.
The first realisation has to be that our electric consumption for everything other than heat, room heating, oven, kettle, is miniscule, I used 68p of electricity yesterday(more than half of which is generally oven or kettle, and on the same day used half of a £10 bag of smokeless nuts in my multifuel stove for heating(I can switch to gas also) as a quick comparison.
If you were to try and heat the average house with electricity, using the same comparison it would be 68p and ?...it would take some self generating system, it it exists, to produce enough electricity for that particular house.
But I am in the process of rebuilding it from the inside out, half of it is currently ripped out and being insulated to modern spec(it was built in 1882) first reality is insulation and heat retention is the quickest way to get any house down to a low enough energy consumption to make something like electricity even possible, without keeping the heat in forget it.
Likewise if you have very good insulation all options are cheaper and less energy, sounds obvious but most can't just reinsulate their whole house.
As a rough guide I'm 175mm celotex from the cavity then roof, 100mm underfoot, sealed box 100 square meters floor space with a sealed room off it, as per current updated planning permission spec, this is not enough insulation to run electric for heating by a long long way.
The so called green tariffs are a joke – it all goes into the grid anyway, and you can’t tell which bean caused the fart.
This is true, of course, but you can give your electricity bill to a "supplier" who invests all your coins into renewable energy rather than purchasing units from non renewables.
https://www.which.co.uk/news/2019/09/how-green-is-your-energy-tariff/
V2G when it’s at home?
Vehicle to Grid. It means that you can get power out of your EV as well as put power in. The idea being that you tell the system what your mileage requirements are (e.g. commute 20 miles to work and back and possibly the shop, whatever) and then you leave your car plugged in all the time. Then it can fill your car when there's an excess of renewable supply and drain it for the benefit of the grid when there's not enough. But it won't drain it beyond what you say you need.
Related to the storage point I was day-job procrastinating the other day, and went digging around online to see if I could find a UK gov strategy on future electricity supply.
The best thing I came across was the energy white paper published in December, which has some useful stuff (snapshots below).... but is pretty light on detail on how security of supply will be ensured whilst also shifting to renewables. Nuclear still seems to be on the table, but progress on any new stations is slow? Plus the "capacity market" is highlighted as a policy mechanism.... basically seems to be additional payments for guaranteed supply during during peak periods. Storage schemes could do well out of that system I guess. Hopefully a solution emerges from somewhere!
These "Insulate Britain" nutters that have been chaining themselves to roads etc have a point, without insulating UK houses we are simply not going to have a sustainable future, it is the first and key step.
Switch the gas off and the UK's electricity trying to heat leaky homes would drain the grid in an hour.
Vehicle to Grid. It means that you can get power out of your EV as well as put power in. The idea being that you tell the system what your mileage requirements are (e.g. commute 20 miles to work and back and possibly the shop, whatever) and then you leave your car plugged in all the time. Then it can fill your car when there’s an excess of renewable supply and drain it for the benefit of the grid when there’s not enough.
If everyone had an electric car plugged in could it operate as a giant collective battery for the grid?
You mean such as the node distributed plan Tesla put forward.
It's one of the main selling points of the system for me without the brains the battery is useless to me.
You sell at peak and charge at off-peak. The algorithms learn your needs and the local grids demands and schedules your capacity appropriately.
For those of us who's car is rarely at the house at peak times
Remembering of course that there's no such thing as backfeeding to the wider grid. Only the local grid downstream of the transformer hence the browngen derisory price as standard.
If everyone had an electric car plugged in could it operate as a giant collective battery for the grid?
Yes that's the idea.
Just anticipating an ev future and the idea of v2g seems like another added complication on top of planning for when to charge beyond 80% for a bigger journey and when where to charge when out and about. Be a right ball ache if you’ve forgotten to change your v2g schedule and wake up to a car at 60% ahead of a 200m day.
Re load balencing:storage I really like the gravitricy approach. Low geographic footprint, Mechanical with no battery degradation or rare element mining. This is for 24hr cycles though not seasonal length storage to allow solar energy to be released for the winter.
Remembering of course that there’s no such thing as backfeeding to the wider grid. Only the local grid downstream of the transformer hence the browngen derisory price as standard.
Hmm, interesting. But does it not amount to the same thing, backfeeding to the local grid will reduce the amount that needs to be supplied 'forward' through the transformer? I guess it will reduce the flexibility to move power around the network though.
yes but no .
great if theres 200 houses down stream of your transformer on say a housing estate.
less so if like me your looking at the transformer out the front window and can count on your fingers the number of houses it supplies with the majority being unoccupied during peak times.
Right, got you. Peak times are the key thing too. Overnight its obvious that most EVs will be plugged-in and able to accept and store 'excess' power available from the grid. But will enough of them still be plugged-in to really help with the morning and evening peaks? A tricky balancing act to predict and coordinate that!