How We Chose Our Photovoltaic System

One of our early decisions when we started discussing moving to Finland was that we want to strive towards energy autonomy. Nick has lots of experience in DIY biogas (see Biogascentral) so we are eager to test biogas in this cold climate. Besides that we also looked into solar hot water and PV (photovoltaic) systems. Our PV system is now almost up and running, so I thought we'd ought to share what we looked for while shopping for a system for us and how we decided to get the one we did.

Why did we choose PV?

Our first investigation went into solar hot water because Nick has seen in Tamera, Portugal that they are very useful in generating hot water through the sun and heard from many people that they have a good price for value ratio. From his friends in Ireland he heard that even in winter, they still gain about 10 to 20 °C, which means that you don't need gas or electricity to heat from 0° C on. We have to remember that their winters aren't as cold and dark as those in Finland, though.

In our climate, we need to take some more aspects into account. As it gets below 0° C in winter the solar hot water system needed to consist of two circles. One circle of anti freeze added liquid which runs outside through the vacuum tubes and then goes inside and another circle that gets the heat transfered on that then can be used as hot water. As we have electric heating, we couldnt have used the water for heating without a complete redo of our heating, and that's where we decided to let this idea go for now.  

As for wind, we thought about it quickly but as we live in a very windless microclimate on our premises, it was a very short-lived thought.

That was the pointed we started seriously looking into PV.

Choosing our system

The key aspects we looked into while looking into PV systems were

• the right size
• price / KwP (kilowatt peak price)
• self-install or all-in package
• which components were used
• extensibility

Size

In Finland PV systems are not supported by the government with anything, really. Unlike Germany, where the state pays small scale PV owners a guaranteed, decent to very good price for every kilowatt they produce, there is nothing like that in Finland. If you produce excess electricity, you have to agree with your electric company if they will buy it from you and if they do, the price is always much less than what you pay yourself. Also many will now buy your power, but only if you buy more from them than you sell them. So it doesn't make any sense to build big systems with lots of electricity for sale in here.

Basically, we wanted a system which would cover all our electricity needs in the summer, help us out with the heating during spring and fall, and rest under snow the winter months, producing very little to no electricity. After looking into our needs and the economies of scale (comparing KwP prices of different system sizes) we ended up choosing a 4,68 KwP system.

Price

When Nick visited the biogas plant in Gescher, Germany back when we were still there, he had a talk with a PV expert. At that time in Germany the KwP was about 1.300 €. What that means is that each face value KW on your system will cost you around 1.300 € (so a, say, 2 KwP system would cost you about 2.600 € to get). As we started asking for offers from Finnish companies though, it became apparent that the KwP price in Finland would be around 1.800-2.000 € for a fully installed system.

Self-installed or all-in package

Nick did some research on buying the components in Germany and having them shipped to Finland. He found some suppliers with good prices of componens and complete sets of PV systems and tracked their costs and added the shipping costs, which would have been about 800,- € from Germany to Finland for a 4-5 KwP system. Which is quit a lot, as there still would have been the labor cost added to that, as we are not in any way able to install them on our own without guidance.

At the same time I was in touch with a Finnish DIY PV system enterpreneuer who runs the company Aurinkovirta. He organises bulk buying & shipping of systems in Germany and holds workshops to educate  everyone buying with himthrough to install the PV system on their own. We were seriously thinking about this solution, as a great offer from an electricity company came about - they were selling their all-in and fully installed systems with a 30% discount for the first 100 customers.

No, we didn't get that offer, as I was was too slow to make a decision! But what I did do afterwards was to ask some other companies offering PV systems for offers, just to see if that one offer was so brilliant and what kinds of systems were there and how much did they charge for installation.

Components

We asked six companies, of which five answered - four with an offer and one with extra questions. The one with questions got back to us after one month (at that time we had already ordered the system!) I gave them all the data I could, our hoped size of about 4-5 KwP, the build of our roof, our assumed consumption of energy and so on, and received four offers I then compared.

The key differences were almost always the components used (which panels, which inverter) and the labor part. There were differences in the guarantee times of the panels, inverters and the installation, too. Some companies offered 25 years production guarantee on the panels, some 30. Some had 5 years on the inverter, some 10. The brand and the country of origin of the panels and inverters varied - Finnish, German and Chinese panels were offered as well as Austrian, Swiss, German and Swedish inverters. All the panels we got offered were 260 Wp panels - the 300 Wp panels which are getting popular in Germany apparently have not reached the Finnish market yet.

Here's a little overview on what we got offered:

Extensibility

Last but not least we also wanted a system which could possibly be extended later on either on our south-west facing wall, the other side of the roof or on ground. Not all inverters were able to do that so we needed to take that into concideration.

Decision making

We ended up ordering our system from Green Energy Finland, which was actually the quickest company to answer our request. They had a very good price to offer on the hardware as well as a very decent installation price. Their standard inverter was not suitable for extension but an upgrade was no problem. The panels they sell are "contract manufactured by Worldwide Energy and Manufacturing USA Co" which basically means they are made in China, but for us personally that was no problem. The Chinese panel quality is high and there have been no reports on slave labour of solar panels (it's not fast fashion after all). The inverter is from the Swedish company ABB. The panels have 12 years of normal guarantee, 30 years of production guarantee, and the inverter has 10 years guarantee.

It was the good package, quick customer service and the KwP price which made us go with GEF and we have been very happy with our decision as everything has been working well and has gone according to plan.

Check back soon too read the report on how the installation went!