ᐅ Is it still worthwhile to install a solar thermal system when you already have an air-to-water heat pump and photovoltaic panels?
Created on: 16 Dec 2019 13:08
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ludwig88sta
Hello everyone,
We are planning to install a photovoltaic system on the fully south-facing pitched roof of our planned house. Since we also want underfloor heating, an air-to-water heat pump is currently our preferred heating option.
I have read here in the forum that with an air-to-water heat pump, a solar thermal system— which heats water using solar energy—would be unnecessary. In other words, on sunny days, the air-to-water heat pump powered by photovoltaic electricity heats the water more efficiently and cost-effectively, right?
Is this still the current understanding as of 2019, so that with a photovoltaic system plus an air-to-water heat pump, the roof is covered only with photovoltaic panels instead of leaving space for a solar thermal system? How did you approach this?
Thanks in advance and have a great start to the week,
ludwig88sta
P.S.: Side question: if you plan a photovoltaic system on the entire south-facing roof, what type of roof tiles do you use? Naturally, as affordable as possible. What do you think about photovoltaic roof tiles (tiles with integrated photovoltaic modules)? Probably more expensive than installing regular photovoltaic panels on a tiled roof, right?
We are planning to install a photovoltaic system on the fully south-facing pitched roof of our planned house. Since we also want underfloor heating, an air-to-water heat pump is currently our preferred heating option.
I have read here in the forum that with an air-to-water heat pump, a solar thermal system— which heats water using solar energy—would be unnecessary. In other words, on sunny days, the air-to-water heat pump powered by photovoltaic electricity heats the water more efficiently and cost-effectively, right?
Is this still the current understanding as of 2019, so that with a photovoltaic system plus an air-to-water heat pump, the roof is covered only with photovoltaic panels instead of leaving space for a solar thermal system? How did you approach this?
Thanks in advance and have a great start to the week,
ludwig88sta
P.S.: Side question: if you plan a photovoltaic system on the entire south-facing roof, what type of roof tiles do you use? Naturally, as affordable as possible. What do you think about photovoltaic roof tiles (tiles with integrated photovoltaic modules)? Probably more expensive than installing regular photovoltaic panels on a tiled roof, right?
L
ludwig88sta17 Dec 2019 21:13ares83 schrieb:
To avoid constantly heating the water inefficiently to 60 degrees, many heat pumps have a legionella program that runs, for example, once a week. For the rest of the time, the water is kept at around 45 degrees. Does the program then heat the water to 60°C (140°F) briefly but long enough to prevent legionella, or how exactly does this program work?
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ludwig88sta18 Dec 2019 10:37fragg schrieb:
Simply shower 5 minutes longer. Same effect, cheaper, more fun.to always completely use up all the water and thus flush out any Legionella bacteria.
Yes, I need to find out which volume for the hot water system is best to plan for.
L
ludwig88sta18 Dec 2019 10:57ludwig88sta schrieb:
But the risk for a single-family house is rather very low, isn’t it?Yes, I already said that the risk is very low. But never say never. Who knows if the Frauenhofer Institute also considered that nowadays very low supply temperatures are often set. Maybe they assumed temperatures above 60°C (140°F)?