More Power

Our plot in Caithness is not really what you would call developed. The next water line is 2 miles away, and the electricity lines just connect our distant neighbours to the grid.

When I made an enquiry with Scottish Power to get me a grid connection to my plot, I was quite surprised, that I would become the partial owner of the company. At least, this is what you could think, when looking at their price tag.

For the ridiculous amount of 35’000,00+ GBP I would get a grid connection to a single place on my plot. Any other point on the plot, stretching a couple of 100m meters, would have to be installed and paid separately.

This and the news of rising energy prices for the next couple of years made me think. There must be something else we could do, like installing a miniature nucelear power plant on my plot, of have perpetuum mobile generating all the power thatI would ever need.

With nuclear energy out of fashion, and expected Planning Permission to be very unlikely, I actually found the perfect couple of “perpetuum mobile”, seeming just perfect for what I would need. Wind + Solar.

Located at the northern parts of the North Sea, near Wick, wind speed is excellent, as you can see from the map.

Distribution over the year shows, most of the wind is to be expected during autumn, winter and spring.

Furthermore, the actual distribution of wind speed reveals, that 60% of all wind speed is in a usage spectrum for wind turbines:

The problem however, in the summer months, there is probably not enough wind to sustain the amount of needed energy production. And the star of our solar system comes into play: solar power.

According to data from the PVGIS-5 database of the European Commission, the expected irradiation of sunlight at our plot roughly looks like this:

In numbers for the last years 2015 and 2016 that gives some really impressive values:

And as we can see from the curve, the sun just starts to shine more when the wind is more asleep.

According to UKPower a medium household in 2019 used 12’000kWh for Gas and 2’900kWh for Electricity, totalling in about 14’900 kWh per year.

This amounts to the following power consumption for a Medium Household:

• kWh/year 1’4900
• kWh/month 1’241.67
• kWh/day 40.83

With some calcuIations from the wind and solar database, I figured out, that with a 5kW turbine and 5m2 of solar panels I could roughly produce this amount of energy over the year:

So as we can see, this is just not enough to produce enough energy on your own. But it looks very promising. With more Solar, a larger turbine (or more turbines) or just a backup generator this could easily be addressed.

Regarding backup generator. Of course, energy sources like wind and solar are not stable, so we would have to have some battery storage capacity anyway.

A storage capacity for a single day in 3.2kWh blocks would cost roughly 22’500,00 CHF (list price for a Pylontech US3000). Adding the turbine with 40’000,00 CHF, solar panels 5’000,00 CHF and inverters 20’000,00 CHF you easily end up with a total price of 80’000,00 CHF – 100’000,00 CHF.

Electricity costs of roughly 3’500,00 CHF – 4’000,00 CHF per year will take a 25 years to pay off – if at all. And if the energy prices rise (as heard, by 50%), it would still need a 15+ years to reach a break even.

So what does this mean? There is no perpetuum mobile? And better use the grid and pay as you consume?

Probably not. Betting on higher energy prices, rising inflation, smarter and more efficient technology in the future and outages ocurring more often and often, this could really payoff much earlier than one would think.

Plus, it can be taken as an example, that it might actually be possible to produce your own energy without being dependent on anything else than wind and sun.