Solar power ponderings. Considering DIY

Paul_VR6 (Forum Supporter) said:

In PA can't you just buy from a 3rd party electricity supplier that's supplying via wind/solar? I know out our way that's an option but in my locale we're mostly nuke/hydro anyway, with just a little peaking via gas turbine.

I can buy from a third party.  Right now, all the other options are more expensive than my current provider, and it's all a little bit "on paper."  I'm still supplied by the same electrons that come from fossil fuels, it's just that some of my money goes to support a greener company.

I also have net metering, but the law (evidently) says that the company is required to buy back surplus juice, not how much they have to pay for it.  They can charge me 12 cents, but they can pay me 0.002 cents.  The goal at this point is to try and reduce how many electrons I pull from the "dirty" grid with the possible end goal of eliminating it.  If I get to a point where I'm making more than I use, I'll likely store it.

Part of this is also because the utility kinda screwed us last year.  I was paying 8 cents and they sent out a letter that said it was going up to 12 cents, but if you enroll in some plan you could pay 9 cents.  Since I was out of the country for a couple months, I missed the cutoff, so now I'm paying 12 cents.  It's a principle thing.

I don't have a bill in front of me, but average bills are in the $75-100 range.  The couple of warm months I'm here, maybe $120 if I run the A/C.

ShawnG said:

Curtis73 (Forum Supporter) said:

In reply to ShawnG :

Good to know.  I would just have to math some things.  It seems counterintuitive to me to replace my fossil-fuel-based electricity with burning fossil fuels in my house.  Can't imagine I'd feel like I'm hugging very many trees that way.

Where I am, natural gas is much cleaner than the coal they burn for electricity.

I agree.  Much cleaner.  The problem is that it's not the "unclean" part of it that gets to me.  The condensed version is that the energy in hydrocarbons is in the bonds between them.  Combustion releases a fixed amount of energy from each molecular bond.  While some combustions are cleaner (NG) and some are dirtier (coal or oil), it still takes approximately the same number of combusted bonds (and therefore carbon atoms) to produce a unit of work.  It's the carbon I'm trying to limit.  The bottom line that many folks seem to miss is that it isn't about how clean it is, it's that we're dragging carbon up from miles below the surface and dumping it into the air.  For me it's not about clean or dirty, it's about introducing carbon back into the biosphere which has been trapped under ground for a billion years.

I used to date a girl who was so upset that I burned flammable trash like paper plates or old magazines in the campfire.  First, it would otherwise have gone to a landfill where it would have released the same carbon over the next 10 years, and second, it came from the biosphere to start with.  Some tree grew and absorbed all that CO2 first, so it's more of a net-zero thing.

I say all of this as I'm about to go get in my van and drive somewhere getting 16 mpg.  It's ok, because I know I'm a big hypocrite.

In reply to RevRico :

Yeah, but I'd let Taylor Swift get away with more than an ugly old fat guy like myself.

In reply to GIRTHQUAKE :

The circle on the roof is mine.  The circle to the left (west) is not mine.  My property line is about 3' to the left of my driveway.

My only thought as to why they didn't plan panels on the roof circle is because it is a flat/rubber roof and maybe there is some liability about it that they didn't want to tackle?  But if I can find a way to do that properly, I don't mind adding panels to the circle with the #1 in it.

For clarity, my property is like this:  Long and skinny.  0.19 acres.  50' wide and 172' long.

Curtis73 (Forum Supporter) said:

For clarity, my property is like this:  Long and skinny.  0.19 acres.  50' wide and 172' long.

Have you put your address into project sunroof? You might just have to go with that already drawn-up plan.

Any chance of doing ground based in your front yard?

In reply to Curtis73 (Forum Supporter) :

I agree.  Much cleaner.  The problem is that it's not the "unclean" part of it that gets to me.  The condensed version is that the energy in hydrocarbons is in the bonds between them.  Combustion releases a fixed amount of energy from each molecular bond.  While some combustions are cleaner (NG) and some are dirtier (coal or oil), it still takes approximately the same number of combusted bonds (and therefore carbon atoms) to produce a unit of work.  It's the carbon I'm trying to limit.  The bottom line that many folks seem to miss is that it isn't about how clean it is, it's that we're dragging carbon up from miles below the surface and dumping it into the air.  For me it's not about clean or dirty, it's about introducing carbon back into the biosphere which has been trapped under ground for a billion years.

I used to date a girl who was so upset that I burned flammable trash like paper plates or old magazines in the campfire.  First, it would otherwise have gone to a landfill where it would have released the same carbon over the next 10 years, and second, it came from the biosphere to start with.  Some tree grew and absorbed all that CO2 first, so it's more of a net-zero thing.

I say all of this as I'm about to go get in my van and drive somewhere getting 16 mpg.  It's ok, because I know I'm a big hypocrite.
 

It sounds like you just want solar. It doesn't make any sense financially, and if you want to limit your CO2, there are many other ways to put your time and money to more efficient use. That's okay, if you want solar, get solar. 
 

I think you should double check into what net metering means in your area, I don't think you have it right. Net metering usually means that you "sell back" energy that you overproduce at any given moment at the same rate that you are charged. Up to the point where you produce more than you use over a given period of time. Any excess they usually pay for at a minuscule rate. So homeowners aren't going to make money on solar by selling excess production, but they should be able to get pretty close to zeroing out. If payback was your priority, you would size to around 85-90% of your use. If cutting carbon is your priority, you can pay extra to get close to 100%. Unless you have time of use charges, adding batteries does nothing save money or reduce CO2. You already have a big, cheap battery available, the grid. So what if the grid is dirty? Any clean energy you send to it is still clean. If you want to produce 100% of the energy you consume, just oversize your solar a bit, it would still be cheaper and cleaner than adding a battery. Cutting yourself off from the grid is just doing the same thing in a different way. There is no net change to how clean the power you use is- the additional battery would actually be increasing your carbon footprint. 

In reply to Curtis73 (Forum Supporter) :

A couple things to check when doing your layout

1) Make sure you don't have any local set back requirements. Many areas require setbacks at the sides of the roof or along peak. 
2) Any modules facing North will greatly suffer in output. Not only will the individual modules put out less, but they will fall out of the window of where the inverter even turns on for a greater length of time. 
3) Don't just look at module prices, look at module dimensions to see which ones make the best use of your roof space. It used to be just 60 cell resi or 72 cell commercial. Now they have all kinds of sizes by the half cell. A long and skinny module might be a little more than a short and wider one for example, but you might be able to fit more of them. 

SV reX said:

Any chance of doing ground based in your front yard?

I don't really want that visual, but I'd be open to it if the township is down for it.

I have never seen a ground-based solar setup in my neck of PA, which makes me think it's not allowed, but I have no real info to back that up.

In reply to Boost_Crazy :

Your logic about the carbon makes sense.

On the financial side, I'll just have to put together a budget and see when the payout meets the payback.  I know if I just called up a company and had them put in a $40k system,  I would be dead twice before it paid for itself.  If I can do it without paying the overhead, I'll just have to math it out and weigh it against my tree hugging desires.

There are fees on my utility bill for delivery and maintenance, but I'm 90% sure they are proportional to my kWh use.  If they were a flat fee, it would suck.

Boost_Crazy said:

In reply to Curtis73 (Forum Supporter) :

A couple things to check when doing your layout

1) Make sure you don't have any local set back requirements. Many areas require setbacks at the sides of the roof or along peak. 
2) Any modules facing North will greatly suffer in output. Not only will the individual modules put out less, but they will fall out of the window of where the inverter even turns on for a greater length of time. 
3) Don't just look at module prices, look at module dimensions to see which ones make the best use of your roof space. It used to be just 60 cell resi or 72 cell commercial. Now they have all kinds of sizes by the half cell. A long and skinny module might be a little more than a short and wider one for example, but you might be able to fit more of them. 

1) Setbacks for anything else on the roof are 5', just like anything on the ground.  My house is currently 5' from the east boundary, so for instance, I couldn't add a chimney or punch out the wall to add a bathroom or something.  I'll make sure that applies to solar as well, but initial research suggests that basically as long as it's not hanging out over the roof in a way that puts it closer than 5', it's ok.

2) Agreed.  Not sure what they were thinking.  I would not put panels on #3.  I would find a way to put them on #1

3) wise.  That and Will Prowse video reviews of panels.  That's pretty eye-opening.

Also investigating some better roofing, like maybe steel.  This roof is about 25 years into a 30 year shingle, so I would want to re-do that before adding panels.

Curtis73 (Forum Supporter) said:

SV reX said:

Any chance of doing ground based in your front yard?

I don't really want that visual, but I'd be open to it if the township is down for it.

I have never seen a ground-based solar setup in my neck of PA, which makes me think it's not allowed, but I have no real info to back that up.

There's a company in Hellertown I've spoken to that specializes in ground mount systems. I'm pretty sure they offer installations out by you when I spoke to them about their range. They have some crazy German groundscrew system for the mounting the panels which goes up a lot faster than installing the old I beam systems that they used to sink and concrete into the ground.

My office has a 48KW ground mount system that provides something like 80% of our power overlooking the Lehigh Valley. It's 13 years old at this point and is still close to rated output. The only problem I've had with it is the meter shorting out for some reason, and one of the inverters failed at one point.

Honestly, I wouldn't even put in a roof mount system these days unless I was doing both a roof and installing a GAF shingle-type system at the same time. They're a pain in the ass to install and if you don't do it when you replace the roof, it's possible the roof will have issues before the system does. Which, of course, greatly inflates the cost of the new roof. It's just like roof mounting an AC unit. Berkeley that noise all together.

I'll also add that there are bucket types of mounts that aren't permanent. You just set them on the ground, fill them with rocks, and wire up the panels. The grocery store near me did a massive install with them recently. It's a pretty cheap way to get the panels up and running and then put in a more elaborate engineered racking system later down the line. (Which is probably what I'm going to do at home.)

This type of thing except I'd buy the cheaper ones on Aliexpress or something. It's still way cheaper than an engineered aluminum or steel ground mount to get started.

In reply to Curtis73 (Forum Supporter) :

I get it. Ground based solar is an eyesore. 
 

But your lot is awful. A ground based system would capture the area that is being poorly utilized in your front yard.  It would make maintenance of the system super easy. You'd avoid all the potential roof leak issues.  Future roof repairs would be easier. 

Snow on the panels?  Sweep it off.

And if you used a bucket mount system, you could take your solar with you if you ever moved.

Might want to check with your local FD as well.

Some of them (so I've been told) won't send crews into a burning building with a solar array on the roof because of the concerns of extra weight up there.

Your stuff might not matter but I'd like it if someone made the effort to drag me out of the building if such a situation arose.

In reply to Curtis73 (Forum Supporter) :

1) Setbacks for anything else on the roof are 5', just like anything on the ground.  My house is currently 5' from the east boundary, so for instance, I couldn't add a chimney or punch out the wall to add a bathroom or something.  I'll make sure that applies to solar as well, but initial research suggests that basically as long as it's not hanging out over the roof in a way that puts it closer than 5', it's ok.

The setbacks are from the roof edges and peak, not the property line. They are usually set by the local fire code. They are so that firefighters can access the roof. Ground level shut down is also usually a requirement, but I think that is pretty much standard on inverter systems now. 
 

Ground mount offers more flexibility if you have the room for it, but isn't any cheaper than roof mount. You are just subbing roof penetrations for piers sunk into concrete. Ground mount costs a little more materials wise, but is easier labor wise. Plus no holes in your roof. If you want to keep more of the space useable, like with a solar carport, those get very expensive when going with an engineered prefab solution. DIY should be cost effective if you can get it permitted. 
 

ShawnG said:

Might want to check with your local FD as well.

Some of them (so I've been told) won't send crews into a burning building with a solar array on the roof because of the concerns of extra weight up there.

Your stuff might not matter but I'd like it if someone made the effort to drag me out of the building if such a situation arose.

That is 100% the sort of "information" I'd confirm from the source. Because I highly doubt it. A tile roof is going to weigh more than a bunch of solar panels.

One option for ground mount is to make a carport as noted above. That would be really desirable around here given our summer time temps and strong sun. I'm not sure it makes sense for the lot in question. The sheer amount of shade in that overhead pic of the lot makes me think that a roof mount is the only viable choice. 

I know that when I was discussing panel mounting with my installer, he was going to use concrete blocks as weights for panels mounted on a flat membrane roof. We didn't end up using that spot but it would have been quick with no roof penetration. 

I would try DIY a small system to see how you like it and how your production is. Set up 4 400W panels in a 2S2P 48V system using a MPPT controller. You 4 deep cycle batteries, or build your own lithium. Use it to run freezer and internet during power outages. You can manually switch over an inverter, or get an All in One unit to manage it all and have true backup power. 

 In reply to Dneikirk :

That's actually what I want to set up for my home system too; the other benefit is you no longer have to setup something with your power company, 48v DC is still efficient but also safe (per OSHA) and things like refridgerators or routers being taken off your bill work consistently so you'll be able to size your system to your needs properly. You basically need to nab a cheap Wattmeter to see what your things use in power and then size your panels and battery based on that.

ShawnG said:

Might want to check with your local FD as well.

Some of them (so I've been told) won't send crews into a burning building with a solar array on the roof because of the concerns of extra weight up there.

I don't wanna come off as a jerk, but that's a load of bull. Fire Departments only enter a building in a blaze when they know someone can be saved and if they've got a building where the fire is small enough that it makes sense to do so (rule is, if you see fire on both ends of the home it's basically lost and they're just "containing" it defensively). "Attacking" fires is hella dangerous, more because they're worried about basements and structural collapse.

In reply to The0retical :

Oh that's very interesting. I still can't shake this idea of making my AC solar powered, but roof mount is essentially out of the question because old roof, terrible shade, and my hated of heights. Ground wouldn't get me much better coverage, but it would have, hopefully, the added benefit of less grass to mow. A movable ground based system could even compensate for the sun moving, potentially. 

In reply to GIRTHQUAKE :

That's why I said "so I've been told". It's something I would certainly like to verify before I go ahead.

Sometimes the FD knows more than the municipality on all kinds of building codes.  It's just something they encounter more frequently than a curmudgeonly guy who sits in an office all day.  I know my township had zero clue on permits for a fireplace, but the FD knew all about it.

I like the idea of a small setup to start.  Other than amperage in the conductors, any specific benefit to 48V over 24 or 12?  I'm only thinking about scalability.  If I get 4 x 400w and wire them up in series, then scaling up will likely have to mean 4 additional panels instead of, let's say, "hey, these panels are on clearance and there are only two left."