Smaller photovoltaic system 2 KWp

Hello,

Is a small photovoltaic system worth it to consume the electricity yourself during the day?
Is it correct that turnkey systems can be obtained for about 4500 euros?
We always have a lot of laundry and cooking is done here every day.
Thanks for your advice
Regards Xinette

That is not really worthwhile. The proportion of fixed costs is too high for such a small system. Installation, electrician, scaffolding, inverter – these costs are incurred anyway, and even if the inverter becomes a bit cheaper and the installation perhaps goes faster, the difference will not decrease proportionally to the system size. 2 kWp might be about 1.5 kW output at peak times. That is enough for own consumption but only in summer and only if you can use the appliances at noon and cook at noon – but not at the same time, because at 1500 W minus the base load in the house you are already over the limit with stove OR washing machine and have to buy electricity. From autumn until spring, it hardly covers the base load.

With a realistic 30% self-consumption and an optimistic 1000 kWh/kWp per year, that would be about 600 kWh saved. You save about 150 euros per year with the energy provider – please do the math yourself.

This does not mean that photovoltaics are not worthwhile. I have a system myself and after one year of operation and first bills, I can make some reliable statements about whether it pays off. Yes, it does if the system is as large as possible (but under 10 kWp; otherwise, unfavorable conditions apply) so that you still have enough reserves to convert as much as possible to electricity. Because feeding in is no longer worthwhile, but self-consumption more so. Increasing it is an art form and takes a while, but you can increase self-consumption with targeted measures without relying on storage systems, which unfortunately still do not pay off at all, not even approximately.

For example, we acquired an electric vehicle (Twizy), a split air conditioning system (heating during transitional seasons and cooling in summer), a domestic hot water heat pump instead of an instantaneous water heater is planned (next year), as well as app-controlled wireless sockets for perfect utilization of surplus production.

In the first year from Nov 13 to Nov 14 we took 1890 kWh from the energy provider; before that period it was still 3500. Still, of the 7367 kWh produced (7.28 kWp system), we only consumed about 1200 ourselves. That means we also used less electricity. Well, the Twizy and the air conditioner only came in October 14.

Accordingly, I would advise choosing the system as large as possible to have reserves for self-consumption and to make an energy consumption above the base load possible at all, and for as long as possible during the year (Nov/Dec/Jan still look very dark in this respect, because almost nothing comes in then). Better to take stronger modules if space is tight. Better to banish solar thermal to the facade, where it makes more sense anyway, instead of giving up roof space. Also mandatory: Inform yourself further here in the forum (technology! tax issues!!) and get many quotes – the guideline for prices is 1300-1400 euros per kWp – so with your system size, no 3000 euros! Possibly a bit more due to the higher proportion of fixed costs. But as said – better build somewhat larger, i.e. at least 4-5 kWp.

Hello Elina,

Thank you very much for the detailed reply. Since we are still in the preliminary planning, the scaffold would be standing anyway. Do you have any good companies in Lower Saxony that you can recommend?
Feel free to send them in a private message.
Thank you Xinette

If you buy at all, really consider getting a larger system for a few euros more. For at least 7kwp, it should be clearly under EUR 10,000 net (as an entrepreneur, you get the tax refunded by the tax office)!

I have a recommendation if I may give it here, namely the company Clen Solar, which operates nationwide in Germany. We deal a lot with craftsmen and this was almost the only bright spot for us in 2013 where everything really worked from start to finish and the offer was also good (not the cheapest but also not expensive). Since they have installed hundreds of systems, they were the only company among those we contacted that also had knowledge of shingle roofs and how the fastening must be done there without making the roof leaky. The others only knew tiles. It was also important to us that it was a company with photovoltaics as its main business and not necessarily working locally. Local is actually preferable with craftsmen, but eventually everyone in the village has their photovoltaic system and if you don’t then expand your area of operation accordingly, the company will eventually go bankrupt. This has happened with some providers who had already made us offers. If we had ordered from them, the warranty would have been gone accordingly.

@ Elina
Good company, they operate nationwide in Germany and we were also very satisfied with them.