Electric combi boilers / solar panels / eco heating solutions

The other single panel nearest the cluster of 3 will be facing east

Aaah yeah, that makes sense

Solar install starts Friday.

Should be fully commissioned by next Wednesday.

9.6kwh battery
18x 420w panels

Heatpump is still over a month away.

Is there much point in having solar panels if it is just covering electricity costs? i.e. you still have gas central heating and hot water.

I guess it depends how much electricity you use.

We're around 900 kWh to 1 mWh per month (including two electric cars).
That will go up to around 1.1-1.2 mWh per month when the heatpump is installed.

We use around 650 kWh per month for the EVs which is charged at 7.5p on Intelligent Octopus Go (11.30pm - 5.30am) and is renewable energy which is nice. The remainder is largely used during daylight hours for home working, watching TV, cooking (induction / electric oven). So this is around 11kWh per day. With a 9.6 kWh battery (charged at the 7.5p rate) we can basically run the house at zero cost without solar.

The benefit to solar is twofold - one, in the summer, there will be plenty to both top up the batter and run the house.
Two, we can export at 15p per kWh. This means that we should either be at zero cost or negative for the majority of our heating, cooking, driving, working etc etc.

The total cost of the heatpump, solar & battery is around £15k.

If we use historical costs for the house of around £3.5k per year for gas & electricity, then payback is only 4.2 years. Moving forwards beyond that timeline, it'll be a saving.

Obviously that's perfect scenario but in your situation, a battery and solar could zero out your energy bill and provide payback in a similar time period depending on usage.

Best thing to do is understand your current usage and spec a system that would be net zero or positive return and they calculate payback time. If it's under 10 years then it's probably worth it.

TLDR: Maybe

Exciting.

Panels go on the roof tomorrow. Battery (not pictured) and grid connection Wednesday.

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Looks like I should probably do some sums. No electric car so usage is far lower at ~ 350kwh per month (although I'd potentially shift some of the heating cost to electric from gas if that was working out cheap).

Gut feeling is it's probably getting up to 8-10 years payback so a bit extended (and still unsure if a loft conversion is going to be done at some point in which case a fair bit would have to change).

I did the maths, and in our case, factoring in battery lifespan (~10 years), PV panel degradation etc, payback basically never comes… ongoing maintenance cost just means you’re kicking the can down the road.

We’re still planning on getting PV & battery at some point down the line, more for environmental reasons than financial due to the above.

Had Octopus round today to rip out the gas meter and cap off the supply, in anticipation of imminent ASHP install.

Feels v cute to ditch the mainline of Siberian earthfarts.

Nice. Ours is being removed a week after the ASHP is installed at the end of feb.

Looking forward to getting rid of it.

Felt cute might regret later

Nah jokes, felt great to cap-off our gas.

I even repurposed the pipe from kitchen to front garden to give us an outdoor tap & hose. Bike kinda smells like gas after I wash it but it’s not gone on fire yet so guess it’s fine.

Cheers. It's a shame as I have plenty of roof in the sun but without a heatpump being a viable option it's not really worth it.

Panels up today.

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Batteries, inverter and grid connection ✅

Pulling basically nothing from the grid now whilst the battery discharges.

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So good!

What are the specs of the system again?

Not sure this is overly competitive from
Octopus. Will need a bigger battery for a start. Such a minefield with all the cowboys about.

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.

Thanks!

18 Trina Vertex 415w panels
FoxEss inverter (6kw)
4 Fox MiraHV25 batteries (9.52kWh usable)

I think the quote above excludes a heat pump?

Yes, no heat pump, separate quote for that. They’ll knock £1k off if I place the order in January for the solar part.

That’s not a bad price. Ours was £13k for 6 more panels and 4kWh more battery.

Ha, I did the same at lunch today.

For £8,399 (plus a grand extra off if I order in January) I get:
5x JA Solar 435w panels
A Giv-Energy 5.2kWh Battery
A Giv-Energy Hybrid Inverter
Installation on a Single Aspect roof
Bird-Netting as standard
All electrical components required to complete the install
All scaffolding, delivery and labour costs

Which seems pretty skimpy on the panels

First PV generation over 1kW!

Ideal day with zero clouds but nice to see were able to maintain one person wfh and charge the battery in January.

That’ll all change when the heat pump gets installed but won’t know by how much until March.

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