Is my roof too small for solar panels, what to do?

Uncle_Cuddles

My household are high users of energy (6 adults in 3 bed + loft conversion house with an EV), around 9,000kwh per year of both electricity and gas. I am on Octopus Agile for electricity and gas is on the tracker tariff. My EV and charger (not smart) are both not compatible with Octopus Intelligent Go or any other similar smart EV tariff from other suppliers. My combined electricity and gas cost is around £200/month in summer and £300/month in winter.

My roof faces south-east but I have a loft conversion and a hipped roof, with triangular roof surfaces, with 2 skylights in one of the s-e facing roof sections. I asked Octopus for a quote a couple of years ago and they emailed me to say that they had no available slots in my area and commented that my roof was not the best shape for efficiently accommodating panels, but that is not to say another installer would not be able to work something out.

I went on the Fresh Solar website and drew out my roof and asked to generate estimate and it came back with an error.

Can anyone offer any advice, or recommendations? Thanks!

For info. I am in Merseyside. Below is the outline view of my roof from the Fresh Solar website. The full width of my roof at the s-e gutter line is about 4m + 2m.

RAS

What are the aspects? Roughly NE and NW?

Uncle_Cuddles

The NW ridge is about 4.5m, the NE pitched boundary line is probably about 6-7m but has a chimney stack near the top - its probably about 4m to the bottom of the chimney to the gutter.

squirrelpie

What about a battery instead of solar panels?

Uncle_Cuddles

https://forums.moneysavingexpert.com/discussion/comment/82127011#Comment_82127011

Ideally I panels and a battery. But just a battery is an option, and I would probaby have to switch to an EV tariff, but I keep getting knocked back on the best tariffs because my charger isn't smart, and my car is not on the list of cars they can control the charging of (Kia EV6). Another alternative would be to build a solar panel pergola or other structure (my garden is big enough).

Reed_Richards

I keep getting knocked back on the best tariffs because my charger isn't smart, and my car is not on the list of cars they can control the charging of

The non-smart EV tariffs are not that bad.. They are not as good as the smart ones but the smart tariffs offer more scope for something to go wrong. You could still save a lot of money using a battery to charge at the cheap rate then discharge when electricity is more expensive. Indeed that's mostly what you would do in winter, even if you had solar panels, because in winter there isn't much sun.

debitcardmayhem

One thing strikes me , Gas tracker is possibly a bad option going into heating season unless the orange baby gets a brain . There are those on here who are more knowledgeable than I on panel designs / options , but the pergola idea could work if there is no shading.

lohr500

Is it 9000kWh electricity and 9000kWh gas?

Can you break down the electricity into your half hourly consumption using the Agile data, or by subscribing to the free Bright App?

We have battery storage (supplemented by a DIY 800 Watt plug in solar system) and I charge up the battery overnight on EDF's GoElectric tariff which currently gives 7 hours from 11pm to 6am for 6.99p per kWh.

We switch as much usage as possible to the off-peak period (EV charging, battery charging, immersion heater, clothes washing, dishwasher, etc) and the battery then covers 99% plus of our daytime demand.

If you can work out what you think your daytime usage would be having shifted as much as possible to the off-peak period, you can work out what sized battery you would need to support your daytime demand.
Our daytime demand is circa 12kWh, so our 13.5kWh battery is a good match.
Then get some quotations for battery storage and see if it gives a reasonable payback period.

Battery storage prices have fallen over the past 18 months and so a battery may be a good option for you. Especially if you combine it with a limited number of solar panels.

Be aware though that not all battery systems are the same and the maximum current you can draw at any time is limited by the size of the inverter that is part of the battery system. If for example you switched on an electric oven and a kettle, then a battery with a 3 or 5kW max output would struggle to meet the demand even if it had the storage capacity to cope. It comes down to the additional cost of getting a higher current output battery vs the frequency of that higher level of output being required.

prowla

You could put a roof on your conservatory.

born_again

Why not get a smart charger, so you can get a EV tariff such as IOG? Linked to batteries a cheaper option.👍

QrizB

Why not get a smart charger, so you can get a EV tariff such as IOG?

A smart charger, installed, is about £1000. It'll typically save you 1p/kWh.

OP uses 9000 kWh/yr. If they can save 1p/kWh o. All of those, that's a £90/yr saving. Not really worth spending £1000 to get, IMO.