I really enjoyed this article. The author is clearly very invested in sustainability, but also takes time to mention the practical problems with some of thee implementations he's describing. Which...
I really enjoyed this article. The author is clearly very invested in sustainability, but also takes time to mention the practical problems with some of thee implementations he's describing. Which I appreciate, it keeps it grounded and doesn't come off as "solar can solve everything!".
My home has lost power several times in the last few years for 12+ hours at a time, thanks to intense storms here in the Midwest. I have strong doubts it will get better as climate change accelerates. So I've been contemplating getting some solar to use as backup power. Instead of getting a system to power the whole house, I'm thinking of buying/building a small scale system then can power just the essentials like my fridge. So this article is fairly timely.
I am in the midwest too, and got some panels for exactly the same reasons. Where I live, I can't install big panels on the building, but it's totally fine to set up an array out on the balcony. So...
I am in the midwest too, and got some panels for exactly the same reasons. Where I live, I can't install big panels on the building, but it's totally fine to set up an array out on the balcony. So I have a pair of 100w panels out there, with a line running in and into a little board where I can plug in whatever. At peak, on a sunny day, it's enough that all I use my grid power for is the air conditioner and my gaming PC. I also bought a big battery, the sort you might bring on a camping trip, and have that plugged in too. That battery is big enough that I can use it to keep the lights on in my bedroom until I go to bed, along with using my devices.
At one point, we had a storm that knocked out power for about 12 or 13 hours. During that time I proceeded pretty much uninterrupted; though the panels couldn't generate nearly as much power with it being cloudy, the battery had enough that between the two, I could just continue as I was with a couple lights and my computer running.
I am able to get enough power through the panels to run the gaming PC from it if I wanted to, but it consumes enough that it's difficult to pair really anything else with it and maintain peak performance. So for now I keep that plugged into the wall. But, the panels I got also have a little hub where you can plug more of them in together, so over time I should be able to build out the array and accommodate it just fine. It's worth it to mention though, I live on my own and just have a dog to take care of; it might take significantly more to power all of your stuff both depending what you do and who all is with you. But, as a trial run, might be worth it to pick up a panel and see what you can do with it, I was very pleasantly surprised at how effective it turned out to be.
This is the one I picked up. I haven't been able to try others, so fwiw, I can't compare very well, but from having it outside and using it a bunch I've been very happy with it. On a bright sunny...
This is the one I picked up. I haven't been able to try others, so fwiw, I can't compare very well, but from having it outside and using it a bunch I've been very happy with it. On a bright sunny day, usually pulls between 65 and 70 watts. On an overcast day, it's around 30-35, and even on a rainy day it can still do around 20 or so if it's angled right.
Overall I've been happy to have it. It's consistent, seems durable enough, and isn't the biggest pain to carry around (it weighs about 6.8kg/15lbs). I haven't been able to get the hub thingy and see how well multiple arrays works out, but from the experience with this one I'm willing to try, for sure.
A question I had was what happens to all the energy generated when you aren't using it? If you size your panels for your maximum load, which is a requirement if there is no storage to balance...
A question I had was what happens to all the energy generated when you aren't using it? If you size your panels for your maximum load, which is a requirement if there is no storage to balance things out, then many of the watts produced are not being used. This source says that the energy is dissipated as heat, but I can't find any sources about how that heat compares to the heat radiated by passive surfaces under the same solar load.
The real answer here is efficient, small scale energy storage. The battery tech we have is not efficient, and things that are, like hydro and molten salt, don't scale down or rely on specific geographies. So that's the technology change that I am on the lookout for.
After all, the hoover, washing machine and power drill are not used every day, and if no electrical appliance is connected then a solar panel will not produce power either. Consequently, the amount of electricity produced by the panel will decrease over its lifetime, while the energy needed to manufacture the panel remains the same. This makes the power from a direct solar panel more carbon-intensive.
However, because energy storage in batteries (or the grid-connected alternative) accounts for such a large proportion of the total energy invested, a standalone solar panel can waste quite a lot of energy before it becomes less sustainable than its counterpart with battery storage or grid connection.
Thats going to really depend on the surface. It shouldn't become hotter than a random dark surface unless solar panels are way better at capturing energy than I realize. Also keep in mind that...
This source says that the energy is dissipated as heat, but I can't find any sources about how that heat compares to the heat radiated by passive surfaces under the same solar load.
Thats going to really depend on the surface. It shouldn't become hotter than a random dark surface unless solar panels are way better at capturing energy than I realize.
The real answer here is efficient, small scale energy storage. The battery tech we have is not efficient, and things that are, like hydro and molten salt, don't scale down or rely on specific geographies.
Also keep in mind that they're talking about not modifying voltage or converting to AC or any of that. They're discussing cutting out ALL of that so I'd imagine part of a workable solution would involve finding the right things to power. @litterallytwisted mentions hot water systems and ya, that would be a good use case because it is a form of energy storage.
Here's the bigger problem with their methodologies and assumptions: They're in Barcelona, Spain. Here's their climate chart. Their min annual temp is around 41 F, which is virtually nothing for...
Here's the bigger problem with their methodologies and assumptions: They're in Barcelona, Spain.
Here's their climate chart. Their min annual temp is around 41 F, which is virtually nothing for heating requirements. I rarely turn on the heat when the low is 41F. I have 3 months a year where that is the maximum temperature, and the lows are closer to 10F (-12 C for the non-Americans).
Their max annual temp is below 86F. I rarely kick on the AC until the temp hits 80F for multiple days in a row. Their cooling needs are virtually 0 by comparison.
And I'm in a fairly temperate part of the USA. The heating and cooling needs mostly get more extreme from there.
All of my other energy use is a rounding error compared to my heating needs. And I have a 15kw solar system on my roof.
One thing to keep in mind is that our comfort levels for temperature are relative. We can be more comfortable in warmer weather if we acclimate ourselves to it, but air conditioning prevents that...
One thing to keep in mind is that our comfort levels for temperature are relative. We can be more comfortable in warmer weather if we acclimate ourselves to it, but air conditioning prevents that and normalizes cooler temperature. The same thing works the other way around as well. Acclimating is what humans have done since the beginning.
Granted, this isn’t always an option, especially in hot climates (and especially with global warming!). Heat can be especially insidious since heat exhaustion is cumulative.
I get that. But I learned I could survive year round in Barcelona in shorts, tshirt, a lean-to and a half-decent sleeping bag. There are some neat ideas to be sure in this post, but the core...
I get that. But I learned I could survive year round in Barcelona in shorts, tshirt, a lean-to and a half-decent sleeping bag.
There are some neat ideas to be sure in this post, but the core thesis isn't going to work in any area where hypothermia is a major problem.
It does seem like an ideal candidate. It's one of the most energy intensive things in my house, and the need for it is directly proportional to the amount of sunlight available outside.
It does seem like an ideal candidate. It's one of the most energy intensive things in my house, and the need for it is directly proportional to the amount of sunlight available outside.
Due to the Canadian wildfires, we have had many days this summer of 90°+ heat with little to no sunlight penetrating the smoke. I get what you're saying, but even without the fires we get many hot...
Due to the Canadian wildfires, we have had many days this summer of 90°+ heat with little to no sunlight penetrating the smoke. I get what you're saying, but even without the fires we get many hot days with little sunlight here in the midwest.
I think I get what you’re meaning here, but unless the smoke is so thick that it feels like evening/dusk/nighttime in the middle of the day, you’re still getting a lot of light coming through....
with little to no sunlight penetrating the smoke
I think I get what you’re meaning here, but unless the smoke is so thick that it feels like evening/dusk/nighttime in the middle of the day, you’re still getting a lot of light coming through. Remember, panels don’t care whether they have direct line-of-sight to the sun unimpeded, they just convert photons into electricity.
Sure, there’s a bit of loss going from clear skies direct sunlight, into indirect light on an overcast day (or a similarly “overcast” smokey haze situation), but you also lose some efficiency just from increased ambient temperatures (in Australia, on a clear day, you can sometimes get better output in winter than in summer, just because of temperatures — even though summer has light for so many more hours)
That is basically what solar panels did this spring/summer. Last year I generated enough credit to tide me over until November but this year it was mostly just keeping my electricity bill break even.
That is basically what solar panels did this spring/summer. Last year I generated enough credit to tide me over until November but this year it was mostly just keeping my electricity bill break even.
I had a pretty big distraction part way through the article where they showed a chest fridge (as opposed to a chest freezer). It is incredibly obvious to me that the chest style would be much,...
I had a pretty big distraction part way through the article where they showed a chest fridge (as opposed to a chest freezer).
It is incredibly obvious to me that the chest style would be much, much more energy efficient than the standing style (at a small cost to convenience). It is why I have a chest freezer at home. I have never seen a chest refrigerator advertised anywhere and very much want one. I am curious if I could just fiddle with the thermostat on a freezer, or if there are some additional functions needed on a fridge or a freezer that would make that less feasible.
Fridges have to care about water management and defrosting while running, that's functionality a freezer doesn't have. Also I suspect running a freezer way outside its intended temp range is not a...
Fridges have to care about water management and defrosting while running, that's functionality a freezer doesn't have. Also I suspect running a freezer way outside its intended temp range is not a good way to save energy, their efficiency rating is only valid for typical use.
I had to laugh a little when he said that game consoles could only be used during the day under direct solar. I get it, but that's just not how they get used. If it's daytime, chances are I'm...
I had to laugh a little when he said that game consoles could only be used during the day under direct solar. I get it, but that's just not how they get used. If it's daytime, chances are I'm working, not playing games.
Something to consider is that this concept requires everything in your home be DC-powered, or else you have to decrease efficiency to convert to AC. That decrease is nothing compared to the inefficiencies introduced by today's energy storage technologies, but it's worth noting just the same.
You could just convert to all DC-powered appliances, but I'm not sure how feasible that is for everything at present. There's a sizable market for RV/camper appliances, but quality is often hit-or-miss, appliances are sometimes too small or fragile for sustained domestic use, and initial purchase costs are often higher due to the scale of production. All of these issues could be resolved by increased demand in the product category over time, though.
There is an AC photovoltaic effect and it was first demonstrated in 2017 at Georgia Tech: https://onlinelibrary.wiley.com/doi/10.1002/adma.201907249 I don’t think there are any AC solar panels...
I don’t think there are any AC solar panels commercially available, though. Also unsure if there are any significant engineering challenges to overcome, but the point is I wouldn’t assume that the only way to achieve what you describe is with a rectifier.
Sounds like this this is this is at technology readiness level 1 and also requires mechanical moving parts. I don't expect much further research here either, since they didn't measure bother...
The active area of the device is about 0.8 cm 0.8 cm. The measurement was set up under illumination of a 442 nm wavelength laser and an optical chopper was positioned to regulate the light switching on and off at a fixed frequency
I don't expect much further research here either, since they didn't measure bother measuring efficiency (probably because it was about 0), and because inverters can be up to 98% efficient. The chopper frequency was also only 1kHz, while it is easy to generate AC power at 10s of kHz using solid-state switching components.
It also has to be something that is ok to not run for days at a time. You could switch to mains power but that requires either direct interaction or a sensing unit that can switch automatically....
It also has to be something that is ok to not run for days at a time. You could switch to mains power but that requires either direct interaction or a sensing unit that can switch automatically. The entire circuit has to switch too since you cannot let the solar ever share with the main line. So it's conditionally useful but generally not.
I really enjoyed this article. The author is clearly very invested in sustainability, but also takes time to mention the practical problems with some of thee implementations he's describing. Which I appreciate, it keeps it grounded and doesn't come off as "solar can solve everything!".
My home has lost power several times in the last few years for 12+ hours at a time, thanks to intense storms here in the Midwest. I have strong doubts it will get better as climate change accelerates. So I've been contemplating getting some solar to use as backup power. Instead of getting a system to power the whole house, I'm thinking of buying/building a small scale system then can power just the essentials like my fridge. So this article is fairly timely.
I am in the midwest too, and got some panels for exactly the same reasons. Where I live, I can't install big panels on the building, but it's totally fine to set up an array out on the balcony. So I have a pair of 100w panels out there, with a line running in and into a little board where I can plug in whatever. At peak, on a sunny day, it's enough that all I use my grid power for is the air conditioner and my gaming PC. I also bought a big battery, the sort you might bring on a camping trip, and have that plugged in too. That battery is big enough that I can use it to keep the lights on in my bedroom until I go to bed, along with using my devices.
At one point, we had a storm that knocked out power for about 12 or 13 hours. During that time I proceeded pretty much uninterrupted; though the panels couldn't generate nearly as much power with it being cloudy, the battery had enough that between the two, I could just continue as I was with a couple lights and my computer running.
I am able to get enough power through the panels to run the gaming PC from it if I wanted to, but it consumes enough that it's difficult to pair really anything else with it and maintain peak performance. So for now I keep that plugged into the wall. But, the panels I got also have a little hub where you can plug more of them in together, so over time I should be able to build out the array and accommodate it just fine. It's worth it to mention though, I live on my own and just have a dog to take care of; it might take significantly more to power all of your stuff both depending what you do and who all is with you. But, as a trial run, might be worth it to pick up a panel and see what you can do with it, I was very pleasantly surprised at how effective it turned out to be.
Do you like the panels you got, and would you recommend them?
This is the one I picked up. I haven't been able to try others, so fwiw, I can't compare very well, but from having it outside and using it a bunch I've been very happy with it. On a bright sunny day, usually pulls between 65 and 70 watts. On an overcast day, it's around 30-35, and even on a rainy day it can still do around 20 or so if it's angled right.
Overall I've been happy to have it. It's consistent, seems durable enough, and isn't the biggest pain to carry around (it weighs about 6.8kg/15lbs). I haven't been able to get the hub thingy and see how well multiple arrays works out, but from the experience with this one I'm willing to try, for sure.
A question I had was what happens to all the energy generated when you aren't using it? If you size your panels for your maximum load, which is a requirement if there is no storage to balance things out, then many of the watts produced are not being used. This source says that the energy is dissipated as heat, but I can't find any sources about how that heat compares to the heat radiated by passive surfaces under the same solar load.
The real answer here is efficient, small scale energy storage. The battery tech we have is not efficient, and things that are, like hydro and molten salt, don't scale down or rely on specific geographies. So that's the technology change that I am on the lookout for.
He does address this point briefly near the end:
Thats going to really depend on the surface. It shouldn't become hotter than a random dark surface unless solar panels are way better at capturing energy than I realize.
Also keep in mind that they're talking about not modifying voltage or converting to AC or any of that. They're discussing cutting out ALL of that so I'd imagine part of a workable solution would involve finding the right things to power. @litterallytwisted mentions hot water systems and ya, that would be a good use case because it is a form of energy storage.
Here's the bigger problem with their methodologies and assumptions: They're in Barcelona, Spain.
Here's their climate chart. Their min annual temp is around 41 F, which is virtually nothing for heating requirements. I rarely turn on the heat when the low is 41F. I have 3 months a year where that is the maximum temperature, and the lows are closer to 10F (-12 C for the non-Americans).
Their max annual temp is below 86F. I rarely kick on the AC until the temp hits 80F for multiple days in a row. Their cooling needs are virtually 0 by comparison.
And I'm in a fairly temperate part of the USA. The heating and cooling needs mostly get more extreme from there.
All of my other energy use is a rounding error compared to my heating needs. And I have a 15kw solar system on my roof.
One thing to keep in mind is that our comfort levels for temperature are relative. We can be more comfortable in warmer weather if we acclimate ourselves to it, but air conditioning prevents that and normalizes cooler temperature. The same thing works the other way around as well. Acclimating is what humans have done since the beginning.
Granted, this isn’t always an option, especially in hot climates (and especially with global warming!). Heat can be especially insidious since heat exhaustion is cumulative.
I get that. But I learned I could survive year round in Barcelona in shorts, tshirt, a lean-to and a half-decent sleeping bag.
There are some neat ideas to be sure in this post, but the core thesis isn't going to work in any area where hypothermia is a major problem.
Of course, I wasn’t trying to prove you wrong. I just was pointing out that there is a large audience of people who these ideas apply to.
Air conditioning would be an ideal workload for direct solar, I imagine (and I think the article suggests this).
It does seem like an ideal candidate. It's one of the most energy intensive things in my house, and the need for it is directly proportional to the amount of sunlight available outside.
Due to the Canadian wildfires, we have had many days this summer of 90°+ heat with little to no sunlight penetrating the smoke. I get what you're saying, but even without the fires we get many hot days with little sunlight here in the midwest.
I think I get what you’re meaning here, but unless the smoke is so thick that it feels like evening/dusk/nighttime in the middle of the day, you’re still getting a lot of light coming through. Remember, panels don’t care whether they have direct line-of-sight to the sun unimpeded, they just convert photons into electricity.
Sure, there’s a bit of loss going from clear skies direct sunlight, into indirect light on an overcast day (or a similarly “overcast” smokey haze situation), but you also lose some efficiency just from increased ambient temperatures (in Australia, on a clear day, you can sometimes get better output in winter than in summer, just because of temperatures — even though summer has light for so many more hours)
That is basically what solar panels did this spring/summer. Last year I generated enough credit to tide me over until November but this year it was mostly just keeping my electricity bill break even.
I had a pretty big distraction part way through the article where they showed a chest fridge (as opposed to a chest freezer).
It is incredibly obvious to me that the chest style would be much, much more energy efficient than the standing style (at a small cost to convenience). It is why I have a chest freezer at home. I have never seen a chest refrigerator advertised anywhere and very much want one. I am curious if I could just fiddle with the thermostat on a freezer, or if there are some additional functions needed on a fridge or a freezer that would make that less feasible.
Fridges have to care about water management and defrosting while running, that's functionality a freezer doesn't have. Also I suspect running a freezer way outside its intended temp range is not a good way to save energy, their efficiency rating is only valid for typical use.
I had to laugh a little when he said that game consoles could only be used during the day under direct solar. I get it, but that's just not how they get used. If it's daytime, chances are I'm working, not playing games.
Something to consider is that this concept requires everything in your home be DC-powered, or else you have to decrease efficiency to convert to AC. That decrease is nothing compared to the inefficiencies introduced by today's energy storage technologies, but it's worth noting just the same.
You could just convert to all DC-powered appliances, but I'm not sure how feasible that is for everything at present. There's a sizable market for RV/camper appliances, but quality is often hit-or-miss, appliances are sometimes too small or fragile for sustained domestic use, and initial purchase costs are often higher due to the scale of production. All of these issues could be resolved by increased demand in the product category over time, though.
There is an AC photovoltaic effect and it was first demonstrated in 2017 at Georgia Tech: https://onlinelibrary.wiley.com/doi/10.1002/adma.201907249
I don’t think there are any AC solar panels commercially available, though. Also unsure if there are any significant engineering challenges to overcome, but the point is I wouldn’t assume that the only way to achieve what you describe is with a rectifier.
Sounds like this this is this is at technology readiness level 1 and also requires mechanical moving parts.
I don't expect much further research here either, since they didn't measure bother measuring efficiency (probably because it was about 0), and because inverters can be up to 98% efficient. The chopper frequency was also only 1kHz, while it is easy to generate AC power at 10s of kHz using solid-state switching components.
It also has to be something that is ok to not run for days at a time. You could switch to mains power but that requires either direct interaction or a sensing unit that can switch automatically. The entire circuit has to switch too since you cannot let the solar ever share with the main line. So it's conditionally useful but generally not.