7.3 kW Bi Facial Rooftop Panels: ~7 year ROI: Fact OR fiction?

Screwdriva

Probably the best March for PV on record. 54% increase in generation over March '24 and slightly higher than April '24. (A % of this is down to the larger 5kW inverter). Achieved "net metering" by careful use of Agile + Outgoing 15p.



Import:



Export:

Qyburn

Isn't there a bit of backtracking going on here? You used to be vehemently pushing Solaredge, but that's forgotten now that Tesla's PW3 is flavour of the month.

Screwdriva

Qyburn said:

Isn't there a bit of backtracking going on here? You used to be vehemently pushing Solaredge, but that's forgotten now that Tesla's PW3 is flavour of the month.

I still "vehemently push" SolarEdge for PV only installations (whatever that means) like mine...but for PV + battery installations, no system comes close to the capability of the Powerwall 3 since launch (not to mention return, when combined with Intelligent Flux tariff).  

To highlight this, a 12 panel + SolarEdge system with SolarEdge 10kW battery would cost £11K installed. A PW3 equivalent with 13.5kW would cost £11K. I know which option I'd go with! 

As the industry evolves, I'm sure there will be more flavours to come. 

Hexane

Screwdriva said:

First time I've seen bifacial panels installed over water! 

https://www.ecoticias.com/en/switzerland-covers-alps-solar-panels/6184/

Your setup comes pretty close to being "over water", though?

(that article had slightly too much AI-generation in it for my liking)

Screwdriva

Hexane said:

Your setup comes pretty close to being "over water", though?

Technically, the house is on an island i.e. surrounded by water

Screwdriva

The system generated a whopping 903kWh in April! Previous all time high was in 6/24. Also hit a daily record of 43kWh this month.

Looks like it's going to be a great PV year! 



Import (Agile)


Export (Outgoing Fixed)

Screwdriva

All time records for May/ June '25 with 983 kWh and 1.03 mWh respectively. The system has now generated 4 mWh in the first 6 months of 2025, something which it would struggle to do in the full 12 months prior to expansion.



We've been able to take advantage of Agile's plunge pricing to significantly lower import to 9p per kWh by using our cylinder immersion element to store negatively priced electricity instead of gas, further compounding the savings and reducing wear on the Viessmann 200-W boiler. 

NedS

Screwdriva said:

All time records for May/ June '25 with 983 kWh and 1.03 mWh respectively. The system has now generated 4 mWh in the first 6 months of 2025, something which it would struggle to do in the full 12 months prior to expansion.



We've been able to take advantage of Agile's plunge pricing to significantly lower import to 9p per kWh by using our cylinder immersion element to store negatively priced electricity instead of gas, further compounding the savings and reducing wear on the Viessmann 200-W boiler. 

Impressive