Solar & battery size

ashe

Had a quote off octopus for installation of solar and batteries;

• 5x JA Solar 435w panels
• Giv-Energy 5.2kw Battery
• A Giv-Energy Hybrid 3.6kw 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
• £8399 no VAT

we are a 4 bed detached and fairly high elec users, considering a future EV. currently on octopus tracker but would consider agile for cheap overnight charging for EV/battery

our elec usage is around 5200 units a year/15 kwh a day - it sounds like a fairly small system? She said she will quote me for a larger 9kw battery and on survey we might get away with 7 panels in which case it is £400 extra per panel - our roof is hipped and she said they have to allow 0.4m at the edges

Curious on thoughts as to sizing of battery and solar array? This is in the north east and we have a pretty much directly south facing garden

EssexHebridean

That's interesting to know what the broken down amount for extra panels would be - our quote is for 6, and I am hoping that might increase on survey so it's handy to know what the relative costs for that could be. 

Stars88

A few of our neighbours have had solar panels installed on our South side facing pitched roofs.

Chatting to one of them a few months after install on an overcast day, they told me that the battery would only recharge/top up when there is unbroken sunshine with no cloud, days that are overcast does little to the battery.

I can see why its not particularly useful in this country given how little unbroken sunlight we get per year.

ashe

Stars88 said:

A few of our neighbours have had solar panels installed on our South side facing pitched roofs.

Chatting to one of them a few months after install on an overcast day, they told me that the battery would only recharge/top up when there is unbroken sunshine with no cloud, days that are overcast does little to the battery.

I can see why it's not particularly useful in this country given how little unbroken sunlight we get per year.

TBH I would  be charging the battery up overnight, via octopus agile when it's a low cost and even free sometimes, then using solar during the day while wfh, then use battery evening when prices are higher 

they came back with a 9.3kw battery quote for 9300

zxzxzx

4500 kWh p.a. - 4.75 panels, 3.6 inverter, 2x5.2 batteries. Install about 12k.

Had my installation 10 months ago and with hindsight I would have more panels, larger battery and a bigger inverter, so go big would be my advice. 

My array is south facing and on grey rainy days I still generate electric not enough to charge the batteries necessarily but it contributes to running the house.

ashe

zxzxzx said:

4500 kWh p.a. - 4.75 panels, 3.6 inverter, 2x5.2 batteries. Install about 12k.

Had my installation 10 months ago and with hindsight I would have more panels, larger battery and a bigger inverter, so go big would be my advice. 

My array is south facing and on grey rainy days I still generate electric not enough to charge the batteries necessarily but it contributes to running the house.

are you not on agile so you can charge it at low rates overnight? Sometimes they even pay you for it. soem days it may be 8p, some days 2p. 

QrizB

ashe said:

Curious on thoughts as to sizing of battery and solar array? This is in the north east and we have a pretty much directly south facing garden

That looks expensive to me. Without the battery, your setup should be something like £3k. The battery might be another £2k. I can't see how they get to £8k unless you've got a particularly awkward roof.

See if you can get a quote from someone else, for comparison.

amanda1024

I would go for more panels if you can fit them. Octopus will only install on one aspect, but other installers won’t have the same restriction.

zxzxzx

ashe said:

zxzxzx said:

4500 kWh p.a. - 4.75 panels, 3.6 inverter, 2x5.2 batteries. Install about 12k.

Had my installation 10 months ago and with hindsight I would have more panels, larger battery and a bigger inverter, so go big would be my advice. 

My array is south facing and on grey rainy days I still generate electric not enough to charge the batteries necessarily but it contributes to running the house.

are you not on agile so you can charge it at low rates overnight? Sometimes they even pay you for it. soem days it may be 8p, some days 2p. 

I am on agile paying an average 10.11p p kWh over the last month, during which there have been half hours lots where I was paid 2/3p to use electricity never mind the 8-2p!
Works well for me.