TheolodianMar 4
Might be a good time to whack a few cheeky solar panels on the garage roof before energy prices jump! 🤔😬
Show threadTheolodianMar 5

It’s looking like at least £350 per panel in parts, plus several hundred for labour depending on installation. So maybe 3 panels on micro inverters for a little over £1K, but 8 panels on a string inverter (future battery) would be around £4K. 😳

This is on a flat roof with no scaffolding required. Still considering 3-4 panels, but no chance on more than that.

Show threadTheolodianMar 7

I’ve found a cheap option! Designed for balcony solar, but as that is illegal in the UK they are going cheap. Micro inverters for 4 panels and a 2kWh AC battery for £700 in total! 🤯

https://uk.ecoflow.com/products/stream-microinverter

EcoFlow STREAM Microinverter

Show threadTheolodianMar 7
They also have a range of 2kWh and a 4kWh battery with 2-4 MPPTs built in. It works if you want a small system, nothing really electrified yet. Should pay for itself quite quickly, although the Agile integration seems to require a paid subscription. Less clear if you will still want such a small system after electrification. 🤔
Show threadTheolodianMar 8
OK, the limitation on the batteries is 800W grid input/output, the 1,200W is only to the backup sockets. So 2,000W of solar isn’t useful for very long on a sunny day, with a 2kWh battery. However, it could be useful on less sunny days - especially as a refurb battery with 2kW solar is only £600 + VAT. 🤔🤓
Show threadTheolodianMar 8
However, where I want to put it is in the utility near the gas boiler and the washer & dryer. By connecting them to the backup sockets we could have heat and hot water in a blackout, and we could use more of the solar for laundry - improving our payback. 👍
Show threadTheolodianMar 8
This may be more valuable than I first realised. Because it is fundamentally a balcony setup, the total output to the house wiring of all inverters on the same user account is capped at 800W. You can change regions in the app and get this to 1,200W but adding more kit does not increase the peak output to the grid/house - only to the backup sockets on the units. So you want the big users plugged directly into the units, and then cover other household loads with the 1,200W.
Show threadTheolodianMar 8

More timely info:

https://youtu.be/Na4LTD1M6nw

DIY Solar: We’re Told Never Do This… So I Did

YouTube
Show threadTheolodianMar 9
Sparky was initially dubious, but now curious. He’s coming later this week to take a closer look at doing this. 🤓👍
Show threadTheolodianMar 12

Quote is in, £1,750 fully installed. Fully legit, but no MCS shenanigans. I am to supply the ballast for the buckets. It will back up the gas boiler in a blackout.

That is exactly £1 per Watt of PV, yet also including a ‘free’ 2kWh battery. The round trip efficiency of the battery is pants, but no biggie.

Show threadTheolodian

Panels installed one week after accepting the quote. Kiss my shiny metal bottom MCS! 🖕

Battery/inverter being wired into the consumer unit in the morning. It is tiny, but should make a dent in our bills. 🤞👍

Mar 19 at 4:27pmMastodon for iOS
Show threadTheolodian6d ago
🤓😎
Show threadTheolodian6d ago
There are some tweaks to do to optimise the output, but this is pretty cool!
Show threadTheolodian5d ago

Generated 5.2kWh today on a 1.75kWp array that is fully shaded by 4pm. Quite a good result! 👍

Adjusted the orientation of the panels, should improve the output based on what I’ve seen from 1 sunny day’s data.

Curiously, I have zero access to my export total. Octopus or Bright. 🤨

Show threadTheolodian5d ago

Generated 5.2kWh, but the app says that it only delivered 4kWh to the house. So the round trip efficiency of the battery seems to be quite poor. Early indication is 56%, however that is only based on 1 day’s data. App could also be much better with reporting.

Still used 16.6kWh from the grid yesterday. This compares to 21.3 to 26.2kWh over the last 3 Saturdays, so it is making a noticeable difference. If every day was like yesterday then it would pay for itself in 3 years on current prices.

Show threadSteve Scott4d ago
@theolodian Yeah the power efficiency and "idle" power consumption on the ecoflow is pretty high.
Show threadTheolodian4d ago
@wishy Thanks. I am hoping that the parasitic loss is low. I was aware of the low efficiency, with the battery anyway. I have it connected via a MID meter so if I can be arsed to spin up some Modbus then I can see what it is really doing…