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Solar happenings
- Thread starter vfx
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Norbert
TSLA will win
Let me split the problem in three groups:
1) Those who buy (much) more electricity than they feed in with solar
2) Those who feed in (much) more than the buy.
3) Those who are about even
Group 1 should not be a problem since they pay very much like other consumers.
Group 2 should not be a problem since the utility, after subsidies, apparently pay a lower feed-in tariff than the the amount for which they can sell it. And solar is during day time, so selling it should not be a problem.
Group 3 , which balances out to about zero, could pay some minimum to be "fair", but I doubt there are enough in this group to make this a real problem. It is only a burden on the infrastructure if a lot were to produce during the day and consume during the night, rather than match their own consumption. But even then, consumption off-peak helps balance the load on the power plants, which is usually much stronger during the day, so that is partially a positive effect.
So considering what was reported above, I'd have some doubts that this is really about fairness. Is it always precisely fair up to this point? One could easily think that the real concern of utilities might be that they want to avoid encouraging solar on roofs, since that a) implies change they need to adapt to, and b) increases the amount of self-sustaining energy use, as if they had fewer customers.
However, EVs go with solar power, and EVs mean additional demand. Or are utilities going to reduce the demand charges for EV fast-chargers? Then I'd be listening.
1) Those who buy (much) more electricity than they feed in with solar
2) Those who feed in (much) more than the buy.
3) Those who are about even
Group 1 should not be a problem since they pay very much like other consumers.
Group 2 should not be a problem since the utility, after subsidies, apparently pay a lower feed-in tariff than the the amount for which they can sell it. And solar is during day time, so selling it should not be a problem.
Group 3 , which balances out to about zero, could pay some minimum to be "fair", but I doubt there are enough in this group to make this a real problem. It is only a burden on the infrastructure if a lot were to produce during the day and consume during the night, rather than match their own consumption. But even then, consumption off-peak helps balance the load on the power plants, which is usually much stronger during the day, so that is partially a positive effect.
So considering what was reported above, I'd have some doubts that this is really about fairness. Is it always precisely fair up to this point? One could easily think that the real concern of utilities might be that they want to avoid encouraging solar on roofs, since that a) implies change they need to adapt to, and b) increases the amount of self-sustaining energy use, as if they had fewer customers.
However, EVs go with solar power, and EVs mean additional demand. Or are utilities going to reduce the demand charges for EV fast-chargers? Then I'd be listening.
sp4rk
Banned
Ok, I am looking for a sticky ... can't find.
Completely ignorant as to the how, why and where of solar.
Illinois.
Trying to determine how to recharge ANY EV with solar.
Obviously I would normally be charging overnight ... so it sounds like I am SOL?
But during the day ... how many "panels" would I need to keep the batteries charged up for either an S or a Leaf?
Can one store the energy in batteries? And can one then use a 240v inverter to power my Level 2 chargers?
And if I were to go all the way, and use AirCon during the day, would a size-proportioned roof full or cells be enough to stay off the grid?
Completely ignorant as to the how, why and where of solar.
Illinois.
Trying to determine how to recharge ANY EV with solar.
Obviously I would normally be charging overnight ... so it sounds like I am SOL?
But during the day ... how many "panels" would I need to keep the batteries charged up for either an S or a Leaf?
Can one store the energy in batteries? And can one then use a 240v inverter to power my Level 2 chargers?
And if I were to go all the way, and use AirCon during the day, would a size-proportioned roof full or cells be enough to stay off the grid?
roblab
Active Member
I am sure we have installers lurking here, but here is what I have:I put 60 125watt panels on my roof, which power my house, wells, and car. How many panels depends on how much you drive, and how much your house uses, and also how big the panels are.
At the time CA paid half the price. I got 2 inverters, and they feed 220v into the grid during the day, and the grid pays me for day rate power. At night, I buy back cheap night rate power to charge. The goal is to have enough panels to equal your usage so your yearly bill (at "true-up") is zero. Summer you gain on billing, winter you lose some, so it is measured only once a year.
But any reduction in electric bills is welcome: Some have only a few panels. I try to use less power at day rates (Noon to 6PM) when rates are near triple night rates.
Where I live, there are power outages several times a year, from minutes to days. I bought a bunch of batteries (sealed absorbed glass mat, no maintenance, roughly 18 year life) and added charge controllers to my system. I *could* charge at night from my batteries, but I make more money selling day rate power to the grid and using night rate power to charge. The batteries are only for those days if and when the power is out: We never know without looking since it switches over in a few thousandths of a second. Some feel it is not worth while to add batteries, and I agree: It is purely peace of mind to know the well and other pumps will run for the 97 year old gramma who lives with us, no matter what the grid is doing.
This thread is about Solar news. There are others that help build solar systems for electric cars.
Robert, I was referring to the power companies and the grid. Are they pulling a "Charge Point" type move y getting federal subsidies to build and then charge for smart (and dumb) grid work?
Robert, I was referring to the power companies and the grid. Are they pulling a "Charge Point" type move y getting federal subsidies to build and then charge for smart (and dumb) grid work?
This appears to be a game changer that could revolutionize solar power production and make solar power affordable for nearly everyone. The oil companies are going to hate it. Now, if only we can figure out how to cheaply store the energy.
The 99.7% apply to the amount of sunlight passing the protecting glass. There is some sunlight lost in reflection and absorption in the glass. Perhaps similar optical enhancements can be made to the glass. Most promising to me is make the optical transition between glass and silicon wafer as smooth as possible.
The drawback of higher absorption of the Si cell is higher operating temperatures. There is output loss of 0.5% with every 1°C of temperature increase. I can see this effect on a windy day, that helps cooling my PV array (higher overall output), or if the clouds move quickly and sunshine returns on a cooled-down array, leading to spikes.
Overall I don't expect black Si cells to take PV output up several percent upwards from the current 20% or so State of the Art.
The drawback of higher absorption of the Si cell is higher operating temperatures. There is output loss of 0.5% with every 1°C of temperature increase. I can see this effect on a windy day, that helps cooling my PV array (higher overall output), or if the clouds move quickly and sunshine returns on a cooled-down array, leading to spikes.
Overall I don't expect black Si cells to take PV output up several percent upwards from the current 20% or so State of the Art.
JRP3
Hyperactive Member
Any PV panels that also incorporate liquid cooling/hot water heating? Seems as if it would be a good mix.
CoolPV - Cooled Photovoltaic by ecoTec Energy
WIOSUN GmbH r Photovoltaik
Alibaba (lists a dozen panels from Chinese manufacturers)
First encountered the idea in a report of an Italian refrigerator manufacturer that attached its coolant loops to the rear side of solar module... can't find it right now, perhaps it was in technology review.
Certainly an idea that I will go after for my next solar array, but right now I'm out of roof space...
WIOSUN GmbH r Photovoltaik
Alibaba (lists a dozen panels from Chinese manufacturers)
First encountered the idea in a report of an Italian refrigerator manufacturer that attached its coolant loops to the rear side of solar module... can't find it right now, perhaps it was in technology review.
Certainly an idea that I will go after for my next solar array, but right now I'm out of roof space...
well Volker, you'll just have to build a larger house or design an addition to your currentt house . . . Perhaps a grandmother's cottage.CoolPV - Cooled Photovoltaic by ecoTec Energy
WIOSUN GmbH r Photovoltaik
Alibaba (lists a dozen panels from Chinese manufacturers)
Certainly an idea that I will go after for my next solar array, but right now I'm out of roof space...
On our most recent installation, we used "micro-inverters" on each panel rather than one inverter for each array. The rationale was that each array could only be as productive as the least productive panel whereas each panel with a micro-inverter was independent of the shading that might occur on an adjacent panel. I liked the idea and the rationale seemed solid, but I wonder if other members might have had other experiences with the two different types of inverters.
That is a real benefit to micro-inverters.
Two two main downsides I recall hearing are:
#1: Total system costs tend to be more using micro-inverters.
#2: It can be harder to replace a failed inverter if it is up on the roof under a panel then one mounted on the wall.
(Although one failed micro-inverter doesn't take down the whole system like the "all your eggs in one basket" traditional big inverter approach.)
Two two main downsides I recall hearing are:
#1: Total system costs tend to be more using micro-inverters.
#2: It can be harder to replace a failed inverter if it is up on the roof under a panel then one mounted on the wall.
(Although one failed micro-inverter doesn't take down the whole system like the "all your eggs in one basket" traditional big inverter approach.)
Another BIG benefit of micro inverter would be increased electrical safety. All inverters shut down on power outage, but conventionally built arrays still have up to 800V in their DC lines. That is a real concern for firefighters here.
If I understand correctly, the micro inverters work with DC input voltage of a single panel which is around 40V = harmless.
If I understand correctly, the micro inverters work with DC input voltage of a single panel which is around 40V = harmless.
Yep that and TEG's list are good examples. 800VDC is a bit higher than what you'd see in your typical residential system 300-500VDC is more typical. High voltage DC is also typically said to be more prone to arc-fault fires compared to AC since AC effectively stops arcing with each switch of phase. Certainly in the US working with only 120V potential energy from a hot wire to ground is less dangerous than working with hundreds of DC volts. One drawback of the lower voltage to the roof is that this often requires slightly thicker wires to carry the current. But this is often negated by the fact that you can use plain old Romex instead of THWN2 rated wire in conduit.
With micro-inverters you also get the benefit of per-module monitoring - you can do this with a central inverter as well with add-on modules under each panel - but then it seems to me that you might as well just go with a micro-inverter system.
It's also often easier to expand a micro-inverter system compared to a central system.
Disclaimer: I own a micro-inverter PV system using Enphase micro-inverters.
$109 Billion Increase for Solar in Saudi Arabia
(Not only do they have lots of oil, they have lots of sunlight !)
(Not only do they have lots of oil, they have lots of sunlight !)
I still have trouble seeing anything <115kV as "high voltage", but that's just an occupational hazard with me.:biggrin:
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