4 ms·

I have worked in the solar industry. As a reference, the average efficiency of "normal" solar panels is around 16% today.

galangalalgol 4y ago
Does that mean that in high intensity regions you'd need active cooling or is that not a problem?
- mcronce 4y ago
  This doesn't answer your question, but I really wish someone would offer off-the-shelf panels with tubing on the back to hook up water lines. It would be dope to cool my panels and preheat my hot water at the same time.
  - implements 4y ago
    "Rad" more than "dope" :) I've seen a DIY system where the panels are boxed in, and the hot air created behind the panels used for blown air / heat recovery heating.
  - ilyt 4y ago
    They are usually called "hybrid solar panels" and not exactly a new thing. Usually cheaper to just put more panels tho. Pretty handy if you need to get the most out of roof space but otherwise more panels + heat pump water heater is much simpler solution.
  - bruce511 4y ago
    They exist! For example: https://www.todoensolar.com/epages/61987244.mobile/en_GB/?ObjectPath=/Shops/61987244/Products/pvtcrane&Locale=en_GB https://www.todoensolar.com/epages/61987244.mobile/en_GB/?Ob...
  - duckmysick 4y ago
    There's one combining a heat exchanger and photovoltaics: https://triplesolar.eu/en/introduction/ https://triplesolar.eu/en/introduction/ > The front side of the PVT heat pump panel is similar to a solar panel and has solar cells to generate electricity. The backside is a heat exchanger that supplies the energy source for the heat pump. The heat exchanger-collector collects energy form the ambient temperature and additionally from daylight and sunlight. Not sure how it does throughout the whole season.
- bruce511 4y ago
  So for those not in the know, fun fact, solar panels work better when they don't get hot. So things like airflow for passive cooling do matter. I'm aware of several large-scale solar situated in hot regions with no active cooling, so I guess my answer to your question is no, high effeciency panels in hot environments do not need active cooling. Roof tiles are a different question. There's no airflow underneath them. So they probably get hot. Hot enough to matter? That's hard to say. Do they have the same thermal properties as a regular tile? What is the impact on building temperature? These would be factors to consider during construction. More insulation, better airflow, and do on. Incidentally since they are not flat (at least not in the picture) that likely accounts for the lower effeciency).
  - cmarschner 4y ago
    Would one be able to extract energy out of the hot tiles as electricity? With a heat exchanger?
    - pjc50 4y ago
      Where would you put the cold side?
  - stdbrouw 4y ago
    FWIW, the way roofs are designed these days (at least over here in Belgium) there is supposed to be a little bit of airflow underneath your roof, which is achieved by letting the ridge and hip tiles hover over the roof (instead of cementing them like they used to do) and putting a perforated grate at the bottom just above the gutters instead of boarding it up.
  - iforgotpassword 4y ago
    According to some testing, it matters: https://youtu.be/Mt9qLRN7JvA https://youtu.be/Mt9qLRN7JvA
  - graphe 4y ago
    Fun fact: resistance sucks and makes your electrons bump into protons and crash causing waste heat. Super conductors are usually supercooled and have 0 resistance and every electronic works more efficiently cooler.
jve 4y ago
People, including me were installing panels like crazy last year. They are all 20%+, upto 22-something and did cost me 176€ a piece (that includes VAT).

galangalalgol 4y ago

Does that mean that in high intensity regions you'd need active cooling or is that not a problem?

mcronce 4y ago
This doesn't answer your question, but I really wish someone would offer off-the-shelf panels with tubing on the back to hook up water lines. It would be dope to cool my panels and preheat my hot water at the same time.
- implements 4y ago
  "Rad" more than "dope" :) I've seen a DIY system where the panels are boxed in, and the hot air created behind the panels used for blown air / heat recovery heating.
- ilyt 4y ago
  They are usually called "hybrid solar panels" and not exactly a new thing. Usually cheaper to just put more panels tho. Pretty handy if you need to get the most out of roof space but otherwise more panels + heat pump water heater is much simpler solution.
- bruce511 4y ago
  They exist! For example: https://www.todoensolar.com/epages/61987244.mobile/en_GB/?ObjectPath=/Shops/61987244/Products/pvtcrane&Locale=en_GB https://www.todoensolar.com/epages/61987244.mobile/en_GB/?Ob...
- duckmysick 4y ago
  There's one combining a heat exchanger and photovoltaics: https://triplesolar.eu/en/introduction/ https://triplesolar.eu/en/introduction/ > The front side of the PVT heat pump panel is similar to a solar panel and has solar cells to generate electricity. The backside is a heat exchanger that supplies the energy source for the heat pump. The heat exchanger-collector collects energy form the ambient temperature and additionally from daylight and sunlight. Not sure how it does throughout the whole season.
bruce511 4y ago
So for those not in the know, fun fact, solar panels work better when they don't get hot. So things like airflow for passive cooling do matter. I'm aware of several large-scale solar situated in hot regions with no active cooling, so I guess my answer to your question is no, high effeciency panels in hot environments do not need active cooling. Roof tiles are a different question. There's no airflow underneath them. So they probably get hot. Hot enough to matter? That's hard to say. Do they have the same thermal properties as a regular tile? What is the impact on building temperature? These would be factors to consider during construction. More insulation, better airflow, and do on. Incidentally since they are not flat (at least not in the picture) that likely accounts for the lower effeciency).
- cmarschner 4y ago
  Would one be able to extract energy out of the hot tiles as electricity? With a heat exchanger?
  - pjc50 4y ago
    Where would you put the cold side?
- stdbrouw 4y ago
  FWIW, the way roofs are designed these days (at least over here in Belgium) there is supposed to be a little bit of airflow underneath your roof, which is achieved by letting the ridge and hip tiles hover over the roof (instead of cementing them like they used to do) and putting a perforated grate at the bottom just above the gutters instead of boarding it up.
- iforgotpassword 4y ago
  According to some testing, it matters: https://youtu.be/Mt9qLRN7JvA https://youtu.be/Mt9qLRN7JvA
- graphe 4y ago
  Fun fact: resistance sucks and makes your electrons bump into protons and crash causing waste heat. Super conductors are usually supercooled and have 0 resistance and every electronic works more efficiently cooler.

jve 4y ago

People, including me were installing panels like crazy last year. They are all 20%+, upto 22-something and did cost me 176€ a piece (that includes VAT).