Good morning, we have some questions. We are building a semi-detached house with a Dimplex Law9 IMR. The conduit for photovoltaic systems has been planned.
Would it be more practical to prepare for solar thermal systems in a semi-detached house instead? We have limited available roof space (two windows are installed on the roof).
We called Dimplex yesterday, but their answer was somewhat vague and seemed to favor photovoltaic systems (I had forgotten to mention the windows and the semi-detached house). Their reasoning was that the heat pump runs efficiently in summer and you mostly need the electricity then, which is generated by photovoltaics. In winter, a photovoltaic system is also more practical because it is more efficient.
What is your opinion?
Would it be more practical to prepare for solar thermal systems in a semi-detached house instead? We have limited available roof space (two windows are installed on the roof).
We called Dimplex yesterday, but their answer was somewhat vague and seemed to favor photovoltaic systems (I had forgotten to mention the windows and the semi-detached house). Their reasoning was that the heat pump runs efficiently in summer and you mostly need the electricity then, which is generated by photovoltaics. In winter, a photovoltaic system is also more practical because it is more efficient.
What is your opinion?
Basically, everyone is correct regarding the discussion about "photovoltaics vs. hot water"... You can use the electricity in various ways or feed the surplus back into the grid. However, it depends on the available roof area. As the original poster mentions, there seems to be very limited roof space.
The effort and cost for a very small photovoltaic system (below 3.5 kWp) usually are not worthwhile. In that case, a solar thermal system with good vacuum tube collectors is preferable. The "base costs" for photovoltaics remain the same: scaffolding, inverter, wiring. The more modules installed, the lower these costs are as a proportion of the total cost, making it more economical.
--> How much roof area can you effectively cover? A standard photovoltaic module is about 1 m x 1.70 m (3.3 ft x 5.6 ft) and delivers between 270 and 350 Wp depending on the model. If you can install at least 10 modules on your roof, then it makes sense to consider photovoltaics seriously.
And yes, in the months of November and December, the system typically produces very little energy. In December 2019 and 2020, I only had about 10% of the photovoltaic yield compared to April. Once you have calculated how many kWp fit on your roof, you can roughly estimate (considering roof pitch, orientation, shading, etc.) the annual yield you can expect in your area.
P.S.: I have both a solar thermal system (vacuum tubes) and a photovoltaic system on my roof.
The effort and cost for a very small photovoltaic system (below 3.5 kWp) usually are not worthwhile. In that case, a solar thermal system with good vacuum tube collectors is preferable. The "base costs" for photovoltaics remain the same: scaffolding, inverter, wiring. The more modules installed, the lower these costs are as a proportion of the total cost, making it more economical.
--> How much roof area can you effectively cover? A standard photovoltaic module is about 1 m x 1.70 m (3.3 ft x 5.6 ft) and delivers between 270 and 350 Wp depending on the model. If you can install at least 10 modules on your roof, then it makes sense to consider photovoltaics seriously.
And yes, in the months of November and December, the system typically produces very little energy. In December 2019 and 2020, I only had about 10% of the photovoltaic yield compared to April. Once you have calculated how many kWp fit on your roof, you can roughly estimate (considering roof pitch, orientation, shading, etc.) the annual yield you can expect in your area.
P.S.: I have both a solar thermal system (vacuum tubes) and a photovoltaic system on my roof.
H
hampshire27 Dec 2020 11:43BauBauNRW schrieb:
I’m also considering building with photovoltaic panels and keep hearing that it’s not worthwhileIt seems this deserves a more detailed look. What exactly is said to be not worthwhile? Just ask when you hear something and do the calculations yourself.Similar topics