Solar powered sewerage biodigester ?

[Jimbouk]

I posted a couple of years back about reducing the electricity consumption of my condor bio digester, the general gist was it is pennies running it and not worth the risk and cost of damage to blower, if it gets blocked up with sludge during off periods. Made sense.

 

Time passes, build still not finished… almost there, mvhc unit, en-suite, external balustrades still needed.

 

I’m paying almost 50p kWh peak and almost 20p KWh off peak, average 38.5p kWh for the next two years.

 

So the blower is now costing the best part of £1 a day, £365 a year

 

The house is empty 80% of the time, so I’m think can I install a small scale solar system to just supplement the mains? Will provide most of the power whilst sunny and house and empty, and contribute a little when house being used.

 

Yes with hindsight I should probably have installed a full scale pv system, with batteries and feed in tariff. I didn’t and don’t have the cash to do so now.

 

Is it is simple as buying a couple of 12volt panels

 

Victron BlueSolar MonoCrystalline Panel 115W-12V

 

https://www.es-store.co.uk/product_details.php?product=PVC-PAN-VE-115MONO&description=Victron-BlueSolar-MonoCrystalline-Panel-115W-12V&cat_desc=Solar-Panels&cat_id=98&show_menu=3

 

 

Victron Phoenix 12v, 800va 230v Sine wave Inverter

 

https://www.es-store.co.uk/product_details.php?product=PH%2012/0800-VE.D-SCHUKO&description=Victron-Phoenix-12v,-800va-230v-Sine-wave-Inverter---Schuko-Plug&manufacturer=Victron&mf=4

 

Then connecting them to the consumer unit, don’t worry as the level of the question suggests, I will not be doing it myself!

 

This would appear to pay for its self in the next couple of years…. Looks too good…

 

I just need to know if it is as simple as that before disappearing down yet another worm hole  

 

Seem to be able to find lots of info on solar systems for off grid camper vans and 5kw on grid, but not much for micro generation on grid.

 

Any thoughts or guidance welcomed, or is it just a case of leave it alone and finish building your house…..

Edited September 1, 2022 by Jimbouk

[SteamyTea]

I don't think that inverter is suitable to be connected to the grid supply.

You also have to inform your DNO that you are connecting a generation set to their supply.

You are on the right track though, just not the right equipment.

[ProDave]

About the cheapest grid tie inverters I know are these from China sold on ebay and no doubt other places https://www.ebay.co.uk/itm/403845542808?hash=item5e0711f398:g:bZ8AAOSwjadjAzoy&amdata=enc%3AAQAHAAAAsDa2%2Bx6zbI%2FStoMKUEkN%2FmztR3vxOG7gTmM79BQEnHvCcZJYHf3fnP6MV7Lsh4RTeMCp1bPJFdbwwKsI51PAyrRrFagqykuonsrZbeW5Lf3H%2FhbnvFNRaajPEGBr6yGqWKq0izsVyavDbLVap2nSjhG8uIQTbEEX%2BdwDuiZllSTmdg49LBESNa0yktViz3UKgP%2FsUz95nh5jGJepCFKhvFJbbymD2XtHpSXVoRPYJv%2B7|tkp%3ABk9SR_rvuf3eYA

 

If you use one of those, don't tell your DNO that is what you have, Although they work, I bet they are not on any approved list.  If you want proper approved kit it will cost more something like this https://www.ebay.co.uk/itm/304513473387?hash=item46e66adb6b:g:3b8AAOSwmRtipKSU&amdata=enc%3AAQAHAAAAoF0vWbg1ae3D7vT5oInPZMXsmO5MnTgFH1lATI3TcfLTIqNmFfzzkfUIRpSdz3E47G7TQpcppPL%2FYyyEa0N1iadNBbT%2BFU64oe9W0a6suJvP0Mhl5Zx5Vqeazkd7j0oNdMojbSOW%2BjWAExfOi2ro7RrfZXYEBve9zbiug%2Bs5y1ZaAqmaQCsoUWT2vdDDJQRCjtezU8G4hgvuJibw307914w%3D|tkp%3ABk9SR4DYzv3eYA

[RobLe]

2KWp of solar vertically mounted in an unshaded south facing location(fence!) will give on average 3(winter) to 5(summer) kWh/day of energy.   You can get panels 2nd hand cheap sometimes.  Suggest using a regular grid tie inverter into your consumer unit (sparky job just for the last bit) and inform the dno.  
You’re already on E7 type tariff, so the pv replaces expensive elec.  Without a battery system or expensive pro install any unused(by you) power is exported free, but later you could add a cheap immersion diverter and get free hot water.

 

[SteamyTea]

1 hour ago, Jimbouk said:

I’m paying almost 50p kWh peak and almost 20p KWh off peak, average 38.5p kWh for the next two years.

Just seen this.  This is a much greater day rate than I pay to EDF on a standard variable, 3 monthly billing supply.

Think I am paying 20p night and 35p day.

Have a look at that first.