We have had the ‘5 solar panels’ each rated at 250W peak production for approx 1 year now and this is a reasonable time to report on the success to date. There have been a number of issues, shall we say, throughout the year.
Covid 19 has of course completely distorted the demand side as there have been few visitors to the villa during 2020.
We had a fibre internet connection put into the villa to increase speeds massively. This disrupted the connectivity to the system so a few months in the middle of the year are unreported.
In summary – total energy generated 1.344 MWhr of which we actually used 1MWhr …the rest being fed back into the Portuguese Electricity Grid. (if we have more occupation of the villa the self-consumption increases).
month | Total Solar Gen (KWhr) | %ge of Consumed | %ge of Solar Used | Saving (€) |
November | 116 | 31 | 88 | 19 |
October | 174 | 57 | 70 | 23.2 |
September | 193 | 15 | 83 | 27.8 |
August | 213 | 12 | 82 | 27.7 |
The last 4 months show an actual saving of between 19 and 27.8 euros per month….which helps payback the initial investment in the panels which were ~ 700€ each and being paid off over 5 years at a monthy cost of approx 65€. If we assume an average saving of 25€ per month under current conditions it would take 65/25 * 5 years to break even ie 13 years.
This number will probably fall as the %ge of self-consumption increases due to a higher occupancy and with some more thought about how to consume energy preferrentially during the day….where possible.
Of course we are primarily trying to reduce the carbon footprint of the villa and that of course has been a considerable success. The panels should keep producing energy for 25 years or more if we are lucky so the long term investment is sound …but of course…a long way off the guesstimations of the EDP predicting a 7 year ROI.
We can all sleep a little easier in our beds knowing we are ‘trying’ to do the right thing.
Dave
Contact me at davebain77@gmail.com if you want to find out more.