Solar power

bflynn

bflynn

Final Approach
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Brian Flynn
Starting a new thread to avoid derailing an existing thread. I know, crazy, right?

Tantalum said:
maybe solar will advance to a point where we all have it
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Solar power has advanced to that point. As a rough rule of thumb, you can capture 1 kW of power from about 30 sq ft of space - that obviously varies by latitude. An average house uses about 30 kW/per day, so 900 sq ft of solar cells are needed, well less than the roof space of that average house.

Unfortunately, the solar industry has not advanced to that point yet. It's highly fragmented and immature and the production viability in the US is limited by excessive regulations...the rules intended to protect us are preventing solar from being realized.

It's a case of NIMBY. Lots of people happy to have solar, but make them in another country, don't pollute mine.
 
bflynn said:
the rules intended to protect utility companies are preventing solar from being realized.
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FTFY...
A friend is looking in to a Tesla solar roof. Those are tempting...
 
I just checked on installing solar where I live. My local electric company advised they do not offer bi-directional meters. So I have a few choices...
Go off grid entirely.
Put some circuits entirely off grid.
Or, install a second meter just for the solar system and sell my power back separately.
They charge me 10 cents per kwh.
They will credit me 2 cents per kwh.

It isn't economically advisable to install where I live unless I go entirely off grid.
 
FORANE said:
It isn't economically advisable to install where I live unless I go entirely off grid.
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Two choices if you still want solar.
1. Install batteries and undersize your total load a small amount. So you do not sell back to the grid. Likely does not pencil out economically.
2. Undersize the panels by a small fraction of your peak draw.

Both cases stay connected, the system is just small enough to significantly reduce the electric bill but not fully disconnect from the utility.

Tim

Sent from my HD1907 using Tapatalk
 
Grid tie systems are troublesome. They force you to turn off your power when their's goes out. I get the safety aspect of it, but there are solutions which protect against you back powering the grid. I agree, power companies do this to make solar less attractive.

The rules I was talking about are environmental regulations. You cannot competitively build solar panels in the US. That limits the industry to what other countries are willing to build. They do it without our environmental regulations so it isn't like we're saving pollution, we're just pushing it somewhere else.
 
bflynn said:
Starting a new thread to avoid derailing an existing thread. I know, crazy, right?



Solar power has advanced to that point. As a rough rule of thumb, you can capture 1 kW of power from about 30 sq ft of space - that obviously varies by latitude. An average house uses about 30 kW/per day, so 900 sq ft of solar cells are needed, well less than the roof space of that average house.

Unfortunately, the solar industry has not advanced to that point yet. It's highly fragmented and immature and the production viability in the US is limited by excessive regulations...the rules intended to protect us are preventing solar from being realized.

It's a case of NIMBY. Lots of people happy to have solar, but make them in another country, don't pollute mine.
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I think there is a lot more to it than just putting 900 sq ft of panels, a lot more. Houses use power 24/7, solar doesn't produce 24/7. In fact a 1kw panel only produces 1 kw under ideal conditions. I haven't delved deeply into it, but I'm thinking you are going to need a much larger capacity panel system, plus a large storage system to make 30 kw/h per day reliably.
 
Of course there is more to a solar system than the panels. In terms of the ability of everyone to have a solar system, the limit is not the technology at your house. Showing how much space is required is just for the purpose of demonstrating that it's a practical amount...you don't need an acre of solar panels to power a house.

Of all the systems out there, I like the Tesla solar roof best right now and will probably look hard at it when we need to replace a roof. Of course, we just redid our about 3 years ago when that wasn't available, such great timing.
 
what's the production capacity of the industry? By that I mean, how many panels can be manufacturered per year? how many panels can be installed? what's the useful life of a panel?

and then there are the questions related to the engineering required for installing panels on a structure (wind loading changes, if any; weight; etc)

and, of course, northern Maine homeowners won't get as much generation as someone in Arizona... by a huge margin.

edit: I'm going to try to get the answers to my own questions. I didn't mean to imply that I expected anyone else to answer those questions... unless they happen to have the answers on the tip of their tonque... so to speak (no pun)
 
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I look on in amazement here in Florida at all the new subdivisions going up. They clear-cut the trees and put in hundreds and hundreds of cookie-cutter homes with tons of direct sunlight. It would be a perfect opportunity to build the homes with sufficient structure and orientation to take maximum advantage of solar roof panels, but not a solar roof panel in site. If they put a $20k solar roof on each home, that would add about $80/month to the mortgage. That would easily be paid for by the monthly electric savings. And those savings would get even larger as the price of electricity inevitably increases.
 
JOhnH said:
I look on in amazement here in Florida at all the new subdivisions going up. They clear-cut the trees and put in hundreds and hundreds of cookie-cutter homes with tons of direct sunlight. It would be a perfect opportunity to build the homes with sufficient structure and orientation to take maximum advantage of solar roof panels, but not a solar roof panel in site. If they put a $20k solar roof on each home, that would add about $80/month to the mortgage. That would easily be paid for by the monthly electric savings. And those savings would get even larger as the price of electricity inevitably increases.
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Maybe, I'd like to see an analysis done on that. Both with and without subsidies and a look at expected actually production versus panel specification.
 
Bob Noel said:
what's the production capacity of the industry? By that I mean, how many panels can be manufacturered per year? how many panels can be installed? what's the useful life of a panel?

and then there are the questions related to the engineering required for installing panels on a structure (wind loading changes, if any; weight; etc)

and, of course, northern Maine homeowners won't get as much generation as someone in Arizona... by a huge margin.
Click to expand...

https://edition.cnn.com/2021/06/09/business/solar-manufacturing-china-ohio/index.html


Tim
 
I just started talking to someone about an install on my hangar. It's a lot of money, but does seem like it's a no brainer, pay for itself type deal....
 
tspear said:
Two choices if you still want solar.
1. Install batteries and undersize your total load a small amount. So you do not sell back to the grid. Likely does not pencil out economically.
2. Undersize the panels by a small fraction of your peak draw.

Both cases stay connected, the system is just small enough to significantly reduce the electric bill but not fully disconnect from the utility.

Tim

Sent from my HD1907 using Tapatalk
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No, can't do that. The local electric company said I can't connect solar system to any circuit that is connected to their meter.
 
FORANE said:
No, can't do that. The local electric company said I can't connect solar system to any circuit that is connected to their meter.
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Not sure they can say that. What area are you in? What company?
 
JOhnH said:
I look on in amazement here in Florida at all the new subdivisions going up. They clear-cut the trees and put in hundreds and hundreds of cookie-cutter homes with tons of direct sunlight. It would be a perfect opportunity to build the homes with sufficient structure and orientation to take maximum advantage of solar roof panels, but not a solar roof panel in site. If they put a $20k solar roof on each home, that would add about $80/month to the mortgage. That would easily be paid for by the monthly electric savings. And those savings would get even larger as the price of electricity inevitably increases.
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Another 20k on the list is another 2-4k on the down payment which is where most people struggle with home buying. Most mortgages are lower than rent (not considering maintenance, utilities, etc).

My guess is with a market where people are buying like crazy they would rather just get the house out on the market at a price more people are eligible for before that demand dries up. Ultimately the consumer decides if solar is important to them when buying and that isn't happening right now. When buying slows, builders may be incentivized to stand out more.
 
FORANE said:
No, can't do that. The local electric company said I can't connect solar system to any circuit that is connected to their meter.
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But I bet you can connect a generator to your house and they're ok with it, right?
 
FORANE said:
No, can't do that. The local electric company said I can't connect solar system to any circuit that is connected to their meter.
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How does a transfer switch fit in that requirement/restriction from your local electric company?
 
I’ve had solar power at my cabin for 25+ years. The system requires battery storage capacity to serve the demand at peak and also in consumption. For us that means 200w of panel and about 1400 aH of storage. The system requires a generator to create power when panels can’t produce enough current and an inverter-charger to manage power in and out of the batteries. Storage batteries are big and expensive. Inverter-chargers adequate to run a house are expensive. Generators capable of running the house are expensive. Off-grid power has been a learning experience. For us to do it in our city houses? Impractical. Very expensive. In a location like Hawaii where utility power is diesel generated and very expensive it might pencil out, but it doesn’t work where my mainland houses are. I would appreciate a solar source for AC but without batteries and all those bring there isn’t an efficiency improvement. We’d just pay more to feel good about having solar.
 
JOhnH said:
but not a solar roof panel in site
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It's nuts isn't it. Absolute gobs of sunlight availability here too, and a generally interested demographic.. they have their Volt, Tesla, whatever in the driveway, the grass free desert scape lawn.. but no panels! Despite there being absurd amount of sun available and near daily emails and alerts from SDGE that they're running out of electricity and you should set your thermostat to 78. I don't understand it.. the other crazy thing? On my current bill, of the $91.03 a total of just $24.72 was actually making the electricity.. the other $66.31 was a host of other fees. Mind you, if you get solar panels, and "sell" power back, many of these charges don't go away. The utility system is heavily designed to keep you plugged in. They don't *actually* care about the environment and green tech.. they're talking points but as the OP points out, the technology is there - it's just being left to languish

FORANE said:
Go off grid entirely
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at least you have that option - for "safety" reasons that is not an option here. You have to stay captive
 
GeorgeC said:
FTFY...
A friend is looking in to a Tesla solar roof. Those are tempting...
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Friend of mine (another aviation writer) bought one. Lives in Florida, so a good place for them. Doesn't have storage capacity, operates off commercial power when the sun isn't out. Of course, when the sun *is* out, he's selling power back to them. Most recent bill was about a tenth of normal.

ROI? He doesn't care. He had the money for the installation, and was tired of being gouged by the power company. Also aware of what's been happening in Texas and California; likes having some degree of independence.

Politics? He's not a tree-hugging leftie, he's a moderate conservative. Truly likes the independence, couldn't care less about environmental impact of their manufacture or what godless country is making them.

I'd consider it myself, but I live in a place where the sun doesn't shine....much of the time, at least.

Ron Wanttaja
 
bflynn said:
. . . Solar power has advanced to that point. As a rough rule of thumb, you can capture 1 kW of power from about 30 sq ft of space - that obviously varies by latitude. An average house uses about 30 kW/per day, so 900 sq ft of solar cells are needed, well less than the roof space of that average house. . .
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Problem is, that 900sq ft (10' x 90' long) needs to be ideally SW-facing in most of the CONUS, and many people don't have that much surface area available on their homes in that orientation (especially on modern homes with architectural roof lines). So, while you may have that much space on your roof, it's usually not all in one area for a single or even a couple of solar arrays. Not to mention the fact that most people don't like the visual-appearance of a bunch of solar arrays bolted to their rooftops.

GeorgeC said:
FTFY...
A friend is looking in to a Tesla solar roof. Those are tempting...
Click to expand...

There has been a lot of unfavorable reports from those who have the Tesla roofing tiles, mainly with damage/failed units and not being able to get customer service to address issues. Still runs into the problem of only really being effective on SW-facing roofing, but it does solve the appearance problem for many, at the cost of larger efficiency losses do to needing individual connections and smaller individual panel size vs a standard array. For the cost, it doesn't make much sense from an actual payback-standpoint.
 
If I ever build new, I will probably use Geothermal for slab heating/cooling first and foremost, as well as putting as much insulation as I can get into it. I could see using a large solar array on a 40x60ish pole barn/shop where I'd have a ton of roof space for the arrays and a dedicated area for the battery bank. I bet I could generate enough power with those panels on the barn to reduce the electric bill, when combined with the geothermal system. It wouldn't likely be able to completely offset anything, especially in the winter months but it would make sense to me in that arrangement.
 
Most us of expect power to be available to meet our demands. To force a utility to buy back excess solar electricity doesn’t provide a savings since they’re still required to have generation capacity to meet peak demand. Politicians may force them to buy it back but that’s politics, not energy management.
 
In my location they will buy back only to offset usage. IOW, if I use 5 KWh at night, they'll buy back up to 5 KWh during the day. So, theoretically you can reduce your bill to only the monthly fees, but never have a credit. That kinda sucks in my situation because I have two meters, so I have to pay two sets of fees....
 
I often wonder why there is not more power produced by wave or tide energy. I guess like solar it costs more for the equipment than it is worth today
 
Here in Northern AZ, solar is getting more popular. Everyone can tie into the grid where it's possible (some areas don't have electric available at all). The solar plans offered by the power company have gotten worse over time. I have an 8KW system and get to sell unused power back to the power company at full retail, but I think newer installations aren't as good. In reality, I have peak and off-peak 'buckets' that collect my contributions and credit me back when I use the power. My monthly bill runs under $40 for AC and heat all year except Feb (everything resets at the end of the year). I'm also just under 5000', so we have more clouds than Phoenix and Tucson along with cooler temps.

I looked into the Tesla wall when I ran out of 'peak' credits last year and ended up with a larger bill. Considering it's happened one time in 6 years, I decided it probably wasn't worth it. For a complete off-grid solution it would be great though. It scales up easily and can be mounted in many places.
 
I agree with what others have said about the environmental costs being offloaded to other countries. While I'm in favor of reasonable environmental regulations, the fact that we don't force our trade partners to follow the same rules means that we just send the manufacturing and pollution to other countries and the net amount created is the same or more than if we had done the manufacturing in the US.
 
AKBill said:
I often wonder why there is not more power produced by wave or tide energy. I guess like solar it costs more for the equipment than it is worth today
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I'm sure there is a lot to be gained from energy derived from tidal/underwater current, but as it's well known, the ocean is a harsh environment. Equipment maintenance and repairs gets expensive when it requires heavy offshore rigs and/or dive teams. Salt-water corrosion, plant/aquatic life contamination, etc. all add to the cost over what a wind-turbine would cost. Not to mention even more difficult environmental regulations about endangered starfish and animal habitats. There has already been a few studies that have noted there might be a not-immaterial reduction in local wind velocity in areas with heavy wind-turbine densities. When they start reducing the flow of ocean currents and tidal activity due to power-generator saturation, it'll probably all but kill the tech (admittedly it would likely require a monstrous amount of underwater installations to make any impact on underwater ocean currents).
 
SoonerAviator said:
I'm sure there is a lot to be gained from energy derived from tidal/underwater current, but as it's well known, the ocean is a harsh environment. Equipment maintenance and repairs gets expensive when it requires heavy offshore rigs and/or dive teams. Salt-water corrosion, plant/aquatic life contamination, etc. all add to the cost over what a wind-turbine would cost. Not to mention even more difficult environmental regulations about endangered starfish and animal habitats. There has already been a few studies that have noted there might be a not-immaterial reduction in local wind velocity in areas with heavy wind-turbine densities. When they start reducing the flow of ocean currents and tidal activity due to power-generator saturation, it'll probably all but kill the tech (admittedly it would likely require a monstrous amount of underwater installations to make any impact on underwater ocean currents).
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They're making a testbed down the street from me. Permits and wiring and everything will be in place so people wanting to test their gear can do it without the usual outlay of having to do all the infrastructure themselves. http://pacwaveenergy.org/
 
chartbundle said:
They're making a testbed down the street from me. Permits and wiring and everything will be in place so people wanting to test their gear can do it without the usual outlay of having to do all the infrastructure themselves. http://pacwaveenergy.org/
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Sounds like a good project to help with some of the R&D costs. Still doesn't make the equipment itself cheap compared to other sources due to all of the requirements to have something survive in the cold, open-ocean environment. I'm all for a diverse energy supply though, as it helps offset risks from land-based generation failures (man-made or mother-nature caused). I really think modern nuclear is a great solution for most locales, and provides a very reliable base load for the grid. Supplement that with nat gas/wind/solar/geothermal/tidal and it should be about as "green" as it gets until fusion is ever viable.
 
FORANE said:
Elizabethton TN
Elizabethton electric
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They have a residential generator policy, which is basically what a solar system is. I really don't think they are allowed to tell you that you can't have solar powering your house, but they do want to make sure you don't back feed the grid.
 
FORANE said:
Elizabethton TN
Elizabethton electric
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I called. They transferred me to an "engineer". They treat solar the same as any local generator. It cannot power the grid when the grid is down. Period. That is the only concern.
Therefore, if you are looking at solar to reduce your bill; size it based on average peak demand. You can price it out, but I highly doubt it is worth building a system for your complete usage and selling back to the utility or installing batteries.
Batteries only make sense if you want backup power and want to be able to run the solar when the grid is down and you are disconnected.

Tim
 
tspear said:
I called. They transferred me to an "engineer". They treat solar the same as any local generator. It cannot power the grid when the grid is down. Period. That is the only concern.
Therefore, if you are looking at solar to reduce your bill; size it based on average peak demand. You can price it out, but I highly doubt it is worth building a system for your complete usage and selling back to the utility or installing batteries.
Batteries only make sense if you want backup power and want to be able to run the solar when the grid is down and you are disconnected.

Tim
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Probably the same guy that I spoke with.
I came to the same conclusion regarding the financial analysis.
Thanks for letting me know and looking into it.
 
And some places add thousands of dollars in cost and months of time with the county/code approval process. All to "protect people". Requires structural, aesthetic, and electrical analysis at the code compliance folks, with permit fees, inspection fees, and typically months to get approval. Plus permits and inspections if anything goes bad in the future and must be replaced.

And that's not even counting the HOA restrictions in many areas.
 
How about an off grid solar system and a gasoline generator to meet peak needs?
 
Sac Arrow said:
How about an off grid solar system and a gasoline generator to meet peak needs?
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I know of one rural/mountain property that has solar and wind off-grid system that's backed up by a generator.
 
Sac Arrow said:
How about an off grid solar system and a gasoline generator to meet peak needs?
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Somebody told me in Florida you can’t go off the grid if you have a meter, but it seems like you should be able to disconnect the house completely from the meter and it’s nobody’s business. Maybe that’s against the building code?
 
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