where next for me with energy storage and extra generation
Posted: Sat Mar 26, 2022 1:05 pm
Hi all, this post might end up being a bit of a long one, so you might want to grab yourself a tasty beverage of choice.
Previously, on Jay moves to the countryside and starts a new life......
Over the past eight years we've renovated our old stone farmhouse and opened a glamping site. It's gone from being a cold damp house to warm-ish and dry, free of draughts and much more comfortable home. in 2015 we put 6kw of solar on the south facing roof along with a 300l thermal store with 2 immersions fed from an Immersun which was later replaced with an Eddi. A Dunsley Yorkshire boiler stove was also connected to the store and so our hot water was 100% free from those two sources.
Heating was provided by the Yorkshire stove along with a Woodwarm double sided stove between the other two downstairs rooms so again, that was free heating as I'm slowly returning 7 acres of old woodland to a more managed and healthy environment and have a large 3 bay wood store. The house originally had 7 storage heaters and, as the renovation progressed, we removed all bar two of them. They cost a great deal to run, even on economy 7 tariff. We work from home full time so having the fires became part of the life style but we didn't expect to stay here into retirement age originally.
As we've decided we're now staying here for the longer term, probably the next 20 years or so, we wanted to have proper central heating as, being an old stone cottage, it does get cold when there's no heating running and, when you get to mid afternoon and realise it's getting chilly, it takes a while to warm up. As we're not on the gas grid and certainly didn't want oil, we were left with heat pump options and, as we're on a little farm, we had ground source installed last autumn.
1000m of pipe went under the field behind the house and a Clausius heat pump. Sadly, the old system that had served us so well had to go as you can't get RHI if a wood stove is connected (unless you want to me metered which would mean less payback). So new hot water tank and radiators all round the house. Despite a few teething issues, it works brilliantly. I've put Tado TRV valves on all the radiators that aren't left open and we can control it all from our phones with each room individually set. Waking up to a warm house is fabulous. All in, the cost was about £41k and we'll get £32k back over the next 7 years, once the RHI payment is approved. This is why we did it now as RHI ends this month and we couldn't really afford it without knowing we had the payback option.
I've just done the figures for the first quarter compared to the same period last year.
In Q1 2021 we used 4650kwh of electricity at a total cost of £840
In Q1 2022 we used 4800kwh of electricity at a total cost of £1211
Our electricity cost went up 62% from Nov 1st. So, we're basically using the same amount of power but have a warm, centrally heated house which is exactly what I was hoping for. However, we've gone from using most of the power at night to most of it during the daytime, which also has cost implications.
The heat pump, according to it's built in monitoring, is using 9kwh/day, 520kwh/month. I'm assuming that's an average over the 5 months it's been running.
Our total energy import last year was 11,668kwh at a cost of £2109. Our solar panels generated 5800kwh, which is bang on what was expected and is doing that year in, year out.
We're also looking to replace one of the two vehicles with an electric car sometime this year, hopefully.
So, now I'm looking at the future and wondering where to go next. I'd like to generate more of our own power and find more efficient ways to store/use it so we're less reliant on grid import as that cost is only going to keep going up and, after the last few months, I think it's worth looking for alternatives to grid supply. Now, I'm not looking at going completely off grid, just to reduce my reliance on it and the cost implications going forward.
We're inverter limited to 3.8kw export by Western Power and, when our poles, cables and transformer had to be replaced by Western Power because of their age, we paid £2k to have the system upgraded from a 16kva supply to twin phase 50kva for some additional future proofing and moved the supply cable underground from the transformer. One phase runs the house and the other phase feeds out to the barns and the glamping site infrastructure.
The first seemingly obvious choice would be to invest in battery storage so that I can use more of the daytime generation into the evening. As we have the heat pump, we use less diverted energy as we generally have a tank full of hot water because the heat pump is running and that makes best use of the electricity as the heat pump has a COP of around . I've not followed battery technology, except for the occasional look at Tesla prices so that's first on the list. Though I'm not sure how cost effective battery storage is currently, I think it will become more cost effective as electricity prices continue to rise.
I can't add more solar for grid connection but I'm wondering about throwing more panels onto the barn roof and using them to charge additional battery storage to feed into the house. Not sure if that's something that can be done easily as the barn is on a separate phase to the house although the cable does feed up from the house to the barn. This is the second thing to investigate as I've seen insurance-replaced solar farm panels on sale occasionally and 10kw of panels would cost about £2500 plus install/fittings etc.
As we work from home and my wife has, due to changed brought about by the pandemic, returned to working full time, we need to ensure that the office continues to be functional. Currently all our computer/network/internet equipment is covered by small UPS units so that occasional short glitches don't throw everything out. We have a small Honda generator that we can hook up to those things easily enough with an extension lead for when work is done on the line elsewhere and we're without power for several hours at a time, this happens occasionally each year. I'm wondering about being able to have the battery system provide power to the house when the grid power it out but that's not the highest priority and I understand it requires different equipment.
Ok, so if you've made it this far, congratulations. What I'd love to hear is any suggestions for going forward or equipment/options to explore as I've not really been taking much notice of advances in this sort of equipment in the past few years and would appreciate any pointers from anyone who's more familiar with it so I can direct my research. Also, am I on the right lines or is it financially unreasonable for what I'm considering.
Many thanks.
Previously, on Jay moves to the countryside and starts a new life......
Over the past eight years we've renovated our old stone farmhouse and opened a glamping site. It's gone from being a cold damp house to warm-ish and dry, free of draughts and much more comfortable home. in 2015 we put 6kw of solar on the south facing roof along with a 300l thermal store with 2 immersions fed from an Immersun which was later replaced with an Eddi. A Dunsley Yorkshire boiler stove was also connected to the store and so our hot water was 100% free from those two sources.
Heating was provided by the Yorkshire stove along with a Woodwarm double sided stove between the other two downstairs rooms so again, that was free heating as I'm slowly returning 7 acres of old woodland to a more managed and healthy environment and have a large 3 bay wood store. The house originally had 7 storage heaters and, as the renovation progressed, we removed all bar two of them. They cost a great deal to run, even on economy 7 tariff. We work from home full time so having the fires became part of the life style but we didn't expect to stay here into retirement age originally.
As we've decided we're now staying here for the longer term, probably the next 20 years or so, we wanted to have proper central heating as, being an old stone cottage, it does get cold when there's no heating running and, when you get to mid afternoon and realise it's getting chilly, it takes a while to warm up. As we're not on the gas grid and certainly didn't want oil, we were left with heat pump options and, as we're on a little farm, we had ground source installed last autumn.
1000m of pipe went under the field behind the house and a Clausius heat pump. Sadly, the old system that had served us so well had to go as you can't get RHI if a wood stove is connected (unless you want to me metered which would mean less payback). So new hot water tank and radiators all round the house. Despite a few teething issues, it works brilliantly. I've put Tado TRV valves on all the radiators that aren't left open and we can control it all from our phones with each room individually set. Waking up to a warm house is fabulous. All in, the cost was about £41k and we'll get £32k back over the next 7 years, once the RHI payment is approved. This is why we did it now as RHI ends this month and we couldn't really afford it without knowing we had the payback option.
I've just done the figures for the first quarter compared to the same period last year.
In Q1 2021 we used 4650kwh of electricity at a total cost of £840
In Q1 2022 we used 4800kwh of electricity at a total cost of £1211
Our electricity cost went up 62% from Nov 1st. So, we're basically using the same amount of power but have a warm, centrally heated house which is exactly what I was hoping for. However, we've gone from using most of the power at night to most of it during the daytime, which also has cost implications.
The heat pump, according to it's built in monitoring, is using 9kwh/day, 520kwh/month. I'm assuming that's an average over the 5 months it's been running.
Our total energy import last year was 11,668kwh at a cost of £2109. Our solar panels generated 5800kwh, which is bang on what was expected and is doing that year in, year out.
We're also looking to replace one of the two vehicles with an electric car sometime this year, hopefully.
So, now I'm looking at the future and wondering where to go next. I'd like to generate more of our own power and find more efficient ways to store/use it so we're less reliant on grid import as that cost is only going to keep going up and, after the last few months, I think it's worth looking for alternatives to grid supply. Now, I'm not looking at going completely off grid, just to reduce my reliance on it and the cost implications going forward.
We're inverter limited to 3.8kw export by Western Power and, when our poles, cables and transformer had to be replaced by Western Power because of their age, we paid £2k to have the system upgraded from a 16kva supply to twin phase 50kva for some additional future proofing and moved the supply cable underground from the transformer. One phase runs the house and the other phase feeds out to the barns and the glamping site infrastructure.
The first seemingly obvious choice would be to invest in battery storage so that I can use more of the daytime generation into the evening. As we have the heat pump, we use less diverted energy as we generally have a tank full of hot water because the heat pump is running and that makes best use of the electricity as the heat pump has a COP of around . I've not followed battery technology, except for the occasional look at Tesla prices so that's first on the list. Though I'm not sure how cost effective battery storage is currently, I think it will become more cost effective as electricity prices continue to rise.
I can't add more solar for grid connection but I'm wondering about throwing more panels onto the barn roof and using them to charge additional battery storage to feed into the house. Not sure if that's something that can be done easily as the barn is on a separate phase to the house although the cable does feed up from the house to the barn. This is the second thing to investigate as I've seen insurance-replaced solar farm panels on sale occasionally and 10kw of panels would cost about £2500 plus install/fittings etc.
As we work from home and my wife has, due to changed brought about by the pandemic, returned to working full time, we need to ensure that the office continues to be functional. Currently all our computer/network/internet equipment is covered by small UPS units so that occasional short glitches don't throw everything out. We have a small Honda generator that we can hook up to those things easily enough with an extension lead for when work is done on the line elsewhere and we're without power for several hours at a time, this happens occasionally each year. I'm wondering about being able to have the battery system provide power to the house when the grid power it out but that's not the highest priority and I understand it requires different equipment.
Ok, so if you've made it this far, congratulations. What I'd love to hear is any suggestions for going forward or equipment/options to explore as I've not really been taking much notice of advances in this sort of equipment in the past few years and would appreciate any pointers from anyone who's more familiar with it so I can direct my research. Also, am I on the right lines or is it financially unreasonable for what I'm considering.
Many thanks.
, the ME300SP would work with your existing setup - but if adding more PV you might want a hybrid inverter.
