Beelbeebub

A bit off topic but I don't think people have range anxiety. They have refueling anxiety. My work vehicle struggles to hit 150miles on a tank (large, old, automatic and petrol) That's less than many electric cars. Am I worried? No. Because I know that even if I have 30 miles left I could find a filling station, I am very unlikely to have to wait more than 5 minutes for a filling slot and it won't take me more than 5 minutes to fill up. I also know that the difference between the cheapest and most expensive fuel is no more than about 10%. I can predict pretty accurately what my cost will be. I have a relatively short range but no anxiety about refueling. Electric cars don't need super long ranges. 200miles is probably enough. They do need a fairly dense network of high speed chargers with a simple and consistent prices. Ironically the shorter ranges (200mikes or less) imply smaller batteries (50kwh or so). In turn this means faster recharge times (as well as lower build costs, lighter weight etc)

There is a key point, the efficiency of converting gas to electricity is 40% (over 50% with the most modern plants running optimally). So if we all converted to electric radiators from gas boilers the net gas demand would shoot up. For every cubic meter saved from being burnt in a boiler 2.5 would be burnt at the power plant. Which is why Heatpumps are fundamental to the switch. As long as the heatpump is more than 250% efficient you end up using less gas by burning it in a power plant, transmitting it to a house and using a heat pump than by using a gas boiler. And (as a bonus) the heat pump doesn't care how you generate the elecreicty. It could come from wind, solar, imports, nuclear, wave, hydro - whatever you want. Burning gas for heat and power isn't a long term option. I will caveat that with - I'm not dogmatic about never burning gas. I can see a future where we have more gas plant capacity than now but it is only used infrequently as a state level backup. The national equivalent of a generator and some petrol cans in your garage

It's capital vs running costs. The house builder sees the capital costs and the running costs.are irrelevant to them except in so much as they might reduce the attractiveness of a property and hence the price. But the property market being what it is the price is set by location rather than running costs.

I mean you could just mandate an efficency of greater than 250% But that does mean a heatpump of some description. I do agree we are being too dogmatic in going down the air to water route. Air to air would be a much better (and cheaper) route.

Except there is some discussion of removing the green levies on elec hence the proposal to reduce the eligibility for the 7.5k grant (as they aren't proposing to stick the green levies on gas) So the elec/gas ratio (which is the important metric) might fall from the current 4.2 times. Green levies make about 15% of the current elec price, so we"d drop from 26p to around 22p. Assuming gas stays the same that's 3.5x ratio. That's an achievable SCOP and That"s before things like time of use tariffs which can drop the price even lower.

It's fair enough that many installers and HP advocates glossed over the fsct that even though HPs are more efficient than boilers the cost differential on regular electric vs gas of around 4:1 means it can be hard to be cheaper than a gas boiler. That said, variable tariffs exist and it is entirely possible to achive break even or better with a well-designed system, ironically one which is often simpler and cheaper than the "giant buffer" installs that seem to be standard. Ultimately we, as a country need to move off gas for heating. Not only is it enviromentally sound, but it will reduce our delendance on gas from unstable parts of the world run by dictators who might not be friendly towards us. This is both a strategic weak point and also puts our economy at the mercy of international gas prices. There are some things we can do to reduce the ratio between gas and electric and we should.

100% agree with the new build. Shouldn't even be a question. And very easy to implement Just change the building regs - set a.date in the not too distant future (a month or two after announcement) where any application after that date must have electric heating with a scop of at least 3.5 (or a similar metric like cop of at least 2.5 space heating at -10C) That should ensure 200k+ installs a year. Which should be sufficient motivation to train a lot of installers and prime the supply chain. Which then makes the aftermarket easier. And with the aftermarket there needs to be a way for Heatpumps to always be cheaper than gas. Obviously dropping the elec price relative to gas would help that.

https://www.theguardian.com/politics/2025/nov/13/hundreds-of-thousands-to-lose-heat-pump-subsidies-in-reevess-budget-plan There are some valid criticisms of the current setup, but cutting it back seems a backwards step. Again I'll wave the flag for spending the same amount but on subsidies to guarentee the cost of heating by electricity and heatpump will never be more expensive than gas. I think it would cost less and speed up rollout.

How old are the panels?

Just to tie this up..... My DNO came out, they poked about, took some measurements and concluded they could change the tap on my transformer. This involved some backfeeding via links to other transformers and de-energizing my transformer, but there was no supply interruption and the change was seamless. Took a week or so to happen. They called to say they had done it. He mentioned they actually found a fault when they did the work which might have been making the spikes worse. Now my normal voltage is high 230's to low 240's and I don't think i've seen over 250. The only question now is: will this allow me to export more!

From your OP i assume you haven't actually built (or modified) anything yet. Just FYI: I have a carport with a 12degre pitch covered in solar (24 panels) Initially I thought of using the panels as the rood covering but couldn't find any way to seal between the panels even for a carport standard of weatherproofing. It was either silicone seals or rubber inserts. There were a few Chinese systems that used extruded aluminum sections as the rafters and "gutters" to catch the water, but that would not be suitable for a house roof. I then looked at the "in roof" tray systems (GSE trays). The wooden roof structure needs lots of additional battens to support the trays and IIRC there is a minimum pitch requirement and I don't think 12 degrees was enough though 20degrees might be). The cost of each tray (or pairs as they have split system now) was not insignificant either. I ended up using a trapezoidal metal roof (think out of town retail park roof/cladding) and then rails attached directly to the roof. It worked really well for construction, 12 degrees is perfectly easy and safe to walk on and the metal roof is nice and robust. The result looks good and wasn't expensive. I didn't worry about the sub optimal roof pitches, the few % loss of output is compensated for by just having more panels I used a s SolaX IES (single phase) 8kw which could handle up to 16kw of panels. They do make a 15kw 3 phase unit that will take 30kw of panels They also make various models that aren't integrated but do have a bit more flexibility on batteries With 30kwp of panels you will easily be able to provide "baseload" power for your house even on dark days. My 11kwp panels provide for the 400w base load of my house even on pretty gloomy drizzly days which is about 3.5% of peak. If you had 30kw you'd be making over 1kw on all but the worst days. Given you have gas heating I can't think why your house would need more than that (unless you bitcoin mine or run an aluminum smelter as a hobby!) As for batteries, if you can export alot there is an argument that you don't need huge batteries - the grid acts as your battery. Even if your import/export prices aren't perfectly aligned (and I don't know how long the Octopus 15p rate will hang about) and you only get (say) half the price for export as you pay for import, it doesn't really matter if you are exporting so much that your export earnings handily pass you import costs.

That is a good looking roof! It really would be a shame to spoil it with solar panels. I think looking at alternative locations, even redesigning any outbuildings yet to be built or building a bespoke structure will yield very satisfactory solar performance and much easier instillation and maintenance, For reference my 24 panel setup structure was 3-4k in materials excluding any ground works (there was an already existing foundation - but the set up could have used a much simpler foundation eg a simple slab or even large concrete pads) and took me about 100 hours to build on my own (would have been less than 40 hours if there were two of us as I spent a lot of time having to temp fix because there was only one of me and god knows how much time going up and down to fetch items that could have been passed up!) The panels and battery were under 12k fully fitted and wired up. Good luck!

given how nice your roof looks, the various hurdles fitting to it and the fact you have to option of garage/ground mount. I would suggest spending the money you would save on calculations, specialists and scaffolding on the garage/ground option. Panels are so cheap now that it's much less important to get the maximum efficiency out of their orientation, just stick more panels on to compensate.

I'd also say with a high power inverter (eg 8kw) you can wire your whole house from the inverter and be immune to power cuts. Depending on manufacturer the cost of the high output inverters is not much on top of the low output ones. Eg a solax 3.7kw plus a battery is £2,975 whilst the 8kw version is £3,050. At that price difference it's an absolute no brainer to go for the 8kw unit and export limit it.