bernie
2020-12-27 11:21:28
- #1
Basically, everyone is right about what is written here regarding "photovoltaics vs. hot water"... You can use the electricity more diversely or feed the surplus into the grid. However, it depends on the roof area. As the thread starter writes here, there seems to be very little roof space available.
The whole effort and the costs for a very small photovoltaic system (below 3.5 kWp) probably do not pay off. Then better a solar thermal system with good vacuum tube collectors. The "basic costs" for photovoltaics are always the same: scaffolding, inverter, wiring. The more modules are installed, the lower these costs are in relation to the total costs and it is more worthwhile.
--> How much roof area can effectively be covered in your case? A standard photovoltaic module is about 1m x 1.70m and delivers depending on the module between 270 and 350 Wp. If you can fit at least 10 modules on the roof, you can start thinking about photovoltaics.
And yes, in the months of November and December, very little power usually comes from the roof. In December 2019 and 2020, I only had 10% of the photovoltaic yield compared to April. If you have calculated how many kWp fit on your roof, you can roughly calculate (roof pitch, orientation, shading, etc.) what annual yield you will have in your area.
P.S.: I have solar thermal (vacuum tubes) and a photovoltaic system on the roof.
The whole effort and the costs for a very small photovoltaic system (below 3.5 kWp) probably do not pay off. Then better a solar thermal system with good vacuum tube collectors. The "basic costs" for photovoltaics are always the same: scaffolding, inverter, wiring. The more modules are installed, the lower these costs are in relation to the total costs and it is more worthwhile.
--> How much roof area can effectively be covered in your case? A standard photovoltaic module is about 1m x 1.70m and delivers depending on the module between 270 and 350 Wp. If you can fit at least 10 modules on the roof, you can start thinking about photovoltaics.
And yes, in the months of November and December, very little power usually comes from the roof. In December 2019 and 2020, I only had 10% of the photovoltaic yield compared to April. If you have calculated how many kWp fit on your roof, you can roughly calculate (roof pitch, orientation, shading, etc.) what annual yield you will have in your area.
P.S.: I have solar thermal (vacuum tubes) and a photovoltaic system on the roof.