u/keepingleft

Just installed a 6kW inverter 18kWh battery (sig) export limited to 5kW. Total of 5.5kWp solar (3.5 from old FIT panels and 2 just installed).

15kW heat pump getting installed on Monday.

Heat loss calculations suggest that my total annual electricity bill for heat pump (including hot water) will be 7500kWh. This would vary across the year so maybe 4-8kWh per day in summer for hot water, 15-20 in spring/autumn, 37 in winter. Could hit 70kWh on a very cold day (seasonal breakdown is courtesy of AI so take with salt).

Existing usage 3200kWh pa.

Predicted generation 4400kWh pa

So I'm going to have to buy 6300kWh. If I can use battery and careful choice of tariffs to cut my unit price in half, I end up with the same electricity costs and no gas costs so a significant saving.

In summer I'd get some outgoing income as well but my focus is very much on buying as little a possible rather than exporting.

Currently paying 25.22/kWh on flexible octopus.

Cosy variable gives me 12.5p for three periods a day, and if above correct I will need three battery loads on those very cold days.

Seems a no brainer. Could potentially use flux in summer for better outgoing rates but I think I've missed this year's sunshine, thanks to Northern powergrid.

Are my sums right? Have I missed any tariffs? As far as I can see cosy is the only one with three low price periods and also has the lowest unit price?

We've finally got an installation date. The quote was for aiko neostar 2s 465w all black ABC n type mono panels, sigenstor 6kW 1ph hybrid inverter, 2x sigenergy 10.0 battery, backup gateway.

I'm just wondering whether there are new models of anything since this and if so whether I should consider asking for the latest versions.

I saw something about something new from sigenergy but maybe that's just an app update?

Paul

We have solar with so called feed in tariff which pays us 25p per kWh generation. We are still on deemed export at 7.64p. we got smart meters 6 weeks ago after a switch to octopus. Heat pump is awaiting installation and additional solar and battery.

Existing solar is 3.5kW the additional will be 2.8. getting 20kWh battery.

Generation in last year 2785kWh.

In last 43 days we have generated 536, exported 248, imported 198.

Do I stay on deemed export for as long as I can or switch now? Will I have to switch once additional solar and battery installed?

I've been putting off getting a smart meter as I have solar with feed in tariff and deemed export of 50%. I also have an immersun that pushes any spare generation to an immersion heater so I export very little.

Have recently switched to octopus for supply as getting a heat pump from them and it makes sense. They obviously want a smart meter installed so have gone with it as it will allow us to use intelligent tariffs.

I've just realised that if we don't tell our feed in tarif provider (good energy) they'll presumably continue to pay us the deemed export.

Is doing this just slightly naughty or problematic?