Solar & Powerwall 2

[Embattle]

In essence repeatedly high daily amounts and Powerwall was at around 60% capacity on the morning of the 23rd which was also a day when home consumption dropped to 13.3 kWh thus at noon it started sending it to the grid until about 19:00. I sort of fixed it the next day by turning the gas boiler off and immersion heater on, which chewed through the electricity rather well.

SunGift Energy was the company we used and the first they did was send around someone to do a survey before anything, they have software which takes into account any shading which in our case on the East side showed a small shading of 0.2% on one panel and 0.5% on another due to a forward roof and where the sun starts on the longer days. We've got no trees near the house to have any effect on the panels, so no shading from that which is good.

The dual sided panels are certainly interesting but they seem better suited to ground application, in essence the ones on a roof will have no gaps better them thus I would suspect little in terms of reflected sunlight reaching the underside.

Well we all would like some with that kind of efficiency but in reality the highest in a lab that has been achieved seems to be about 47% thus don't hold you breath for getting some for your roof anytime soon, maximum on the market seems to be just over 22% but the next step is probably going to be Perovskites which might eventually allow up to 30%.

 

[Embattle]

So with April traditionally being the start of the 500+ kWh months it was nice to see a better figure this year than last, although I suspect looking at early weather forecasts May will be down on last years.

April 2020 - 578 kWh Gen - Self Powered 88% - Energy offset 100%
April 2021 - 639 kWh Gen - Self Powered 92% - Energy offset 106%

 

[Embattle]

So as expected May 2021 was considerably worse than last years:

May 2020 - 773 kWh Gen - Self Powered 97% - Energy Offset 132%
May 2021 - 577 kWh Gen - Self Powered 79% - Energy Offset 92%

I suspect it'll be roughly the same overall come the end of the year, just got to wait and see.

 

[Embattle]

6 Month Comparison:

Jan - Jun 2020 - 2509 kWh
Jan - Jun 2021 - 2409 kWh

 

[Moriath]

6 Month Comparison:

Jan - Jun 2020 - 2509 kWh
Jan - Jun 2021 - 2409 kWh

Bad day for solar today

 

[Embattle]

Bad day for solar today

9.5 kWh, a couple of days like that in June and July so far.

 

[Embattle]

Solar panel myths: five common concerns about solar PV debunked - Which?

We reveal the facts behind common worries about getting solar PV panels for your home

www.which.co.uk

 

[Moriath]

Solar panel myths: five common concerns about solar PV debunked - Which?

We reveal the facts behind common worries about getting solar PV panels for your home

www.which.co.uk

Im always on the edge of buying. Just with a battery to really make use of it. It gets more expensive.

 

[Embattle]

Im always on the edge of buying. Just with a battery to really make use of it. It gets more expensive.

It is worth it without a battery as shown in my previous figures, at least it is if you intend to live there for a long while.

 

[Moriath]

It is worth it without a battery as shown in my previous figures, at least it is if you intend to live there for a long while.

I guess the fact i work from home and am home most of the day would make that better As well.can retro fit a battery

 

[Embattle]

If you work from home you can easily use the power you produce, for example if you are sitting there and it is a sunny day then you put the washing on etc.

 

[Scouse]

Looking at getting my supply point changed (it's in a retarded place - the consumer unit is on the wall at head height as I come in through the door - people bang their heads on it). Want to move it to the back of the house, change the consumer unit (stick it in the utility room), and get the meter changed (from the fucking stick-a-key-in 22p/kWh kind!).

At the same time I figure I may as well ensure that the supply is good in the future for:

A) a solar and battery installation (that I fully expect the national park to tell me fuck off with, but then that might all change in a few years)
B) enough capacity for a few (3 maybe) rapid car chargers (not just fast, if I'm going to pay then I may as well get rapid)
C) enough capacity to run additional accomodation
D) more modern wiring so I can run a generator outside in the event of a power cut that would power the whole house

I've been on to the network operator to discuss moving the ingress point to the outside wall (and an electrician to do the consumer unit work up-front (I've still to contact the metering supplier - it takes all three to be onsite at the same time to ensure minimal energy disruption).

They've been really professional - submitting my initial request for formal quote got me a mail back. Then the next day a phone call to say they've got it and to expect a follow-up call. Then today a follow-up call to discuss my application on a preliminary level. A discussion of the above has led the lady to engage an engineer to give me a ring in a few days - and she's asked me to fill in a few forms regarding maximum demand, informed me that the transformer on my pole will have to be changed as it's not rated for anything other than running a toaster (and certainly nothing upstream).

Hell it's a complicated piece of form. She advised me to get in contact with my appliance supplier - and I said I've not got one - the move of the point, consumer unit and replacement of the meter is the important thing but if they're coming out I want to future-proof so I don't end up having to pay twice when I want to get solar, battery and/or electric vehicle charging points installed.

I guess I'll discuss with the engineer when he rings me in a few days. But it's a conversation I'm looking forward to.

Not paid a penny yet.


Contrast this to the council planning department at snowdonia national park. I filled out a large email detailing a pre-planning application. I burrowed through their website to find a stupid form to fill in and the email address that I needed to submit it to. It comes with a cost ladder, so I rang them up to ask for advice and the girl said "oh, you're not paying? I can't help - you'll need to ask a planner. No they're not in - leave them a message and they'll get back to you" - which I did, and they didn't.

I did some more digging, decided on "rung 2" - so rang 'em back and paid £250 or so. That was 8 days ago. Not even had email acknowledgement that the mail is in a queue to be looked at.

I also know that, because council, they're going to be utter shits about it. Despite me bending over backwards to make things completely obvious - including plans, profile, sitemap, photographs, numbered descriptions, bat survey results.

They'll make basic mistakes left, right and centre that could end up either denying me the ability to do basic stuff (like power or insulate my house in a modern fashion with minimal visual impact - instead forcing me to stick a whacking great gas canister outside that everyone can see, just in time for them to be made obsolete).




Anyway. I've asked the authority whether I can stick a 10kw array in one of my fields. Roof isn't suitable. I've no idea if 10kw is even remotely sensible for a house our size if we run fully off 'leccy. I guess heating in the winter months would be hellishly expensive if it was all electric under floor - especially as we'd not be producing when we needed it - so would probably be drawing from the grid.

Whaddya reckon @Embattle? If they miraculously give the go-ahead, is it even worth pursuing?

 

[Embattle]

@Scouse

So firstly let me say I'm in no way an expert

A) As you say you never know what will be the policy now and I certainly expect the legislation to change more to support such technologies even in the most protected areas, if not then the technologies will improve such as solar roof tiles etc. so the visual impact would be reduced. As for the battery this really won't be affected by planning since it is largely out of sight or inside a building etc.
B) I wonder what you mean by rapid, on a single phase which is the standard for a house you'll only be able to charge a car at a rate of 7kW with 11kW being available on 3 phase but that also requires the car to have the 11kW capability. Remember our homes run on AC and those rapid chargers in public places are DC thus have very high rates of charge not available in homes. In the end a 7kW charge point will fill a battery from near 0% 10-12 hours.
C) I suspect that won't be a big issue if they do some upgrades.
D) Well if you are doing the house wiring it shouldn't be an issue, but a battery will add cover as well if you go that route.

So here are a few graphs from our system as examples of 2020 solar production:



And the two months below showing the best month (July) and the worst month (Dec):



So lets say you get a 10kWh system that'll produce somewhere in the region of 2.5-2.7 times as much energy as mine but you would still need grid electricity a lot in the colder months, we use gas for heating and water and in December the house used an average 21.5kWh (Low 15.1kWh - High 28.2kWh). All forms of heating benefit from good insulation which is now possible on more houses including older houses than in the past, even more so when using electricity to heat via devices such as air sourced heat pumps. However the biggest issue will be the additional required paperwork when you exceed a 4kWp solar system and this may involve considerable additional costs considering the current stand of you power supply, again it is something to check out at the time and see what the options and costs are for all possibilities.

 

[Scouse]

Ta. I'm going to get a local solar pv company to come out so I can talk to 'em. Even if it means dick.

 

[Moriath]

@Scouse

So firstly let me say I'm in no way an expert

A) As you say you never know what will be the policy now and I certainly expect the legislation to change more to support such technologies even in the most protected areas, if not then the technologies will improve such as solar roof tiles etc. so the visual impact would be reduced. As for the battery this really won't be affected by planning since it is largely out of sight or inside a building etc.
B) I wonder what you mean by rapid, on a single phase which is the standard for a house you'll only be able to charge a car at a rate of 7kW with 11kW being available on 3 phase but that also requires the car to have the 11kW capability. Remember our homes run on AC and those rapid chargers in public places are DC thus have very high rates of charge not available in homes. In the end a 7kW charge point will fill a battery from near 0% 10-12 hours.
C) I suspect that won't be a big issue if they do some upgrades.
D) Well if you are doing the house wiring it shouldn't be an issue, but a battery will add cover as well if you go that route.

So here are a few graphs from our system as examples of 2020 solar production:

View attachment 44907

And the two months below showing the best month (July) and the worst month (Dec):

View attachment 44909View attachment 44910

So lets say you get a 10kWh system that'll produce somewhere in the region of 2.5-2.7 times as much energy as mine but you would still need grid electricity a lot in the colder months, we use gas for heating and water and in December the house used an average 21.5kWh (Low 15.1kWh - High 28.2kWh). All forms of heating benefit from good insulation which is now possible on more houses including older houses than in the past, even more so when using electricity to heat via devices such as air sourced heat pumps. However the biggest issue will be the additional required paperwork when you exceed a 4kWp solar system and this may involve considerable additional costs considering the current stand of you power supply, again it is something to check out at the time and see what the options and costs are for all possibilities.

Why do they require more paper work over 4kWp ? Cause they think you sre a generator rather than public user?

 

[Embattle]

Why do they require more paper work over 4kWp ? Cause they think you sre a generator rather than public user?

Well technically you are a provider at any level but under 4kW it is a lot simpler as I believe in general most a DNOs network can handle a sub 4kW return so you just have to inform the DNO but above this level it gets more complicated, it is worth always remembering the hardware in the grid when it comes to homes was really only designed to deliver power not receive it.

Finally yesterday we got a smart meter installed so I might change to a tariff with a cheaper night rate and load the powerwall with energy over night, also get the dishwasher to do its thing in the time slot as well.

 

[Embattle]

Ta. I'm going to get a local solar pv company to come out so I can talk to 'em. Even if it means dick.

Have you looked more at insulation, drafts and windows?

 

[Scouse]

Have you looked more at insulation, drafts and windows?

Whole house renovation, so absolutely.

 

[Embattle]

Managed a nice three day stint this week (Tues-Thurs) without pulling anything except 0.1kWh from the grid, in fact on those days we output nearly 3.5kWh out to the grid.

I do wish the thick cloud yesterday and today would fuck off however.

 

[Scouse]

Spoke to the power supply company. The good news is that our transformer is so old that they have to swap it out for free. The bad news is that 100amps single-phase is the best we can get unless I spend perhaps upwards of 20 grand upgrading 1.2km of overhead cables along their supply route to me.

So, rapid chargers and heat pumps are unlikely to be a thing anywhere rural unless government policy changes.

Coupled with the fact that I'm expecting a hard "no" from the Snowdonia authority this week on any solar implementation and I'm left with probably burning oil. Which is madness.

 

[Embattle]

I'm sure most houses only have 100 amps.

 

[smurkin]

Coupled with the fact that I'm expecting a hard "no" from the Snowdonia authority this week on any solar implementation and I'm left with probably burning oil. Which is madness.

Yeah, I'm on oil too and I hate it tbpfh. It costs a fortune. Old technology.

 

[Scouse]

I'm sure most houses only have 100 amps.

Unfortunately, I'll need more than average as I'm converting the barn into (badly needed) additional living accomodation.

Because of covid we've gone from a 3 bed house to one bed and two offices. The rooms are small so we can't host beds and desks at the same time and we both work from home 100% of the time - so we can't comfortably host family or friends. It's a bit shit when you can't easily have your mum over for xmas.

So - as I'm having to shell out some readies for electrical work I'd like to future proof. For ease I'd ideally want 3 rapid chargers (we already often have 5 or 6 cars on the drive when we host weekends for friends (we've loads of space for their tents, of course!). Potentially a heat pump (I still haven't ruled it out) - and 2x all of the appliances - i.e. 2x washing machines, dishwashers, induction hobs, power showers, lighting systems, central heating systems etc. etc.

Because of environmental considerations I'd like to do the whole lot with electricity. I'm between a rock and a hard place - the national park will likely tell me to fuck off with solar, that leaves me running it down the wires - which is likely also going to be a no because I can't afford to upgrade the overhead wires for 1.2 kilometers to get 3-phase.

That leaves me with oil or gas boilers - new gas boiler installations are being banned from new-build homes from 2025. I don't see why just because I've got older housing I should be exempt from legislation that benefits the environment (we should all be looking at a bill to retrofit tbh (which as a landlord both terrifies me from a financial pov, but would please me at the same time)).

Add to the above - you should really only be running at 80% of your capacity (so 80amps) anyway (from a safety PoV).

Yadda yadda yadda. Long story short - 3 phase, bigger ampage needed really.

 

[Embattle]

I tend to think you are going vastly over the top even considering future proofing, you ultimately have to consider rejigging your plans.

 

[Moriath]

Sounds like you want a commercial setup in a domestic property

 

[Scouse]

I tend to think you are going vastly over the top even considering future proofing you ultimately have to consider rejigging your plans.

Define rejig plans? I hope you're not saying I shouldn't be able to have a home of the size I need?

Loads of properties in the UK have 3 phase - if not always into the property then to the poles as it helps with load balancing - and as we go forward with electric cars and electric heating then that's going to increase, massively.

If we are to go into a future which is supposed to be greener then we need the infrastructure to enable it. No excuses really.

 

[Moriath]

Define rejig plans? I hope you're not saying I shouldn't be able to have a home of the size I need?

Loads of properties in the UK have 3 phase - if not always into the property then to the poles as it helps with load balancing - and as we go forward with electric cars and electric heating then that's going to increase, massively.

If we are to go into a future which is supposed to be greener then we need the infrastructure to enable it. No excuses really.

When you buy a house in the middle of nowhere you cant expect the facilities to be the same as it would be in a town or even a village especially if they run power over ground.

dont you think?

 

[Embattle]

Define rejig plans? I hope you're not saying I shouldn't be able to have a home of the size I need?

Loads of properties in the UK have 3 phase - if not always into the property then to the poles as it helps with load balancing - and as we go forward with electric cars and electric heating then that's going to increase, massively.

If we are to go into a future which is supposed to be greener then we need the infrastructure to enable it. No excuses really.

You can but as you've been told your excessive requirements are going to cost you, that I guess is the price of living in more remote locations. It was sort of like a family friends daughter moving into a remote location and having to deal with a septic tank, which they didn't like in the end so moved again. Just rough ideas but why not reclaim your house for living space and make the out building an office eliminating the need for additional appliances or do you intend to have two separate properties so people can stay in the out building, if so would it make any difference to have it setup on its own power as if it was a separate house or is that not possible?
Also I still don't get why you need so many EV chargers, people don't tend to drive as much as they think and they are also placing more public chargers every where.

The majority of houses do not have 3 phase, even with modern requirements there won't be many people who would need it.

 

[Scouse]

When you buy a house in the middle of nowhere you cant expect the facilities to be the same as it would be in a town or even a village especially if they run power over ground.

dont you think?

Absolutely - it's a fair point and I agree - I don't expect facilities to be the same (I only have to look at the internet connectivity).

But we have 9.6m people - or 17%+ of the population living in rural areas in the UK. We absolutely must have a plan for enabling the proper electrification of this huge swathe of our population in order to meet our climate change objectives. - and as we're electifying transport and heating (removing the burning of petrol, oil and gas) - then we need a plan for infrastructure upgrades. Not just power generation - but power transportation.

I'm 100% willing to meet any costs that come from the road to the house - and the distance from the road near me to my house means the costs I'm legally obliged to meet (with no complaints from me) is bigger than most people's. That's fair enough.

But infrastructure is governmental responsibility (well, not really - it's now "privately" owned power companies that don't want to do the work because it would hit shareholders profits).

So there's a gap - that needs filling, for nearly 20% of the population who need to electrify. And 100amps isn't going to cut it.

You can but as you've been told your excessive requirements

I reject your suggestion that connection to a modern power grid in a rural area is in any way "excessive". Yes, it's cheaper and simpleer to deliver in cities, but we can't leave 1 in 5 of the population with their dicks swinging in the wind, reliant on oil, petrol and gas, when those forms of energy are being urgently phased out.

I'm fifteen grand in for replacing the septic tank with a package sewerage treatment plant. I'm 8 grand in for running modern water piping to the nearest mains. Absolutely 100% take that on the chin as it's on my privately owned land and my privately owned connections.

But electrical connectivity to serve future usage is a minimum requirement - and we have infrastructure companies who are responsible for connecting people to modern infrastructure - and they're leaving rural areas in the lurch whilst paying out to shareholders.

That cannot be allowed to stand in this "green" day and age IMO.

 

[Embattle]

Technically it is exactly the same you are being offered which the majority of people living in non rural areas get, I suspect the only difference is that those in towns/cities areas will probably find it easier and cheaper to get 3 phase. A single phase offers something like 23kW of energy and in the majority of cases even those who need more probably only need it in the rare event everything is on at the same time, I'm interested in what you have listed as the breakdown in terms of your energy requirements.