Shading: Conflicting results

[SunEagle]

I'm not sure what to make of this.

Are you saying that Energy Sage is doing something wrong (e.g. not calculating properly)? That their providers are providing exaggerated estimates of production? That Energy Sage is promoting solar in some unhealthy way (e.g. hyping the benefits without pointing out the drawbacks)?

The part that is hard to understand is that the cost of electricity where you live and CA is about the same. The amount of electricity produced by solar is going to be less where you live then in most of CA based on being farther North.

So unless the installed $/watt is much less where you live then compared to CA it is hard to understand how you will get a payback of less than 5 years where most in Southern CA have a longer payback.

[DanS26]

I think what Mike (and others) are trying to say is that you are putting up a "wasting asset". Putting a solar system on a heavily shaded roof will never perform as designed. That wastes resources. Think of the materials and time invested in aluminum, silicon, copper, pvc, etc that will never be recovered in economic terms. It is a net detriment on the earth resources. And it does not matter how much rebates, tax credits and suspect analysis is made......it is still a wasted asset. Somehow it is a very hard concept for many people to understand.

[rscott]

The part that is hard to understand is that the cost of electricity where you live and CA is about the same. The amount of electricity produced by solar is going to be less where you live then in most of CA based on being farther North.

So unless the installed $/watt is much less where you live then compared to CA it is hard to understand how you will get a payback of less than 5 years where most in Southern CA have a longer payback.

Looking at the numbers, I'm guessing the confusion may be due to SRECs. Factoring in SRECs, in Massachusetts each kWh generated is worth about $.215 (what we pay for electricity) PLUS about $.20-$.40 or so (that we get from SRECs for the first 10 years). So if the payback period is less than 10 years, it's like we are generating electricity worth about $.40-$.60/kWh.

[DanS26]

Looking at the numbers, I'm guessing the confusion may be due to SRECs. Factoring in SRECs, in Massachusetts each kWh generated is worth about $.215 (what we pay for electricity) PLUS about $.20-$.40 or so (that we get from SRECs for the first 10 years). So if the payback period is less than 10 years, it's like we are generating electricity worth about $.40-$.60/kWh.

Yes, we all know the government waste resources too. Some people who qualify benefit from that waste.......but most of us just pay.

[rscott]

Yes, we all know the government waste resources too. Some people who qualify benefit from that waste.......but most of us just pay.

Yes, anyone who goes solar and deducts it on their taxes is benefiting. And some states have their own incentives as well. I'm new here, but my sense is that this isn't the right forum for discussing whether government subsidies are good or bad.

[Sunking]

Great thoughts there. No on turning off all electrical appliances after the sun goes down, but yes on not driving an ICE vehicle (and like many EV owners, cannot imagine going back).

Those EV owners took the bait. It is now known EV produce more pollution than an ICE vehicle. What the population in the USA does not know, shush its a secret, is to make an EV especially the battery, plus the power used to generate electricity produces more CO2 emission than a large luxury ICE car produces in 10 years on the road. Once you factor in no EV battery can last 10 years is no contest.

Oops!

[CharlieEscCA]

Looking at the numbers, I'm guessing the confusion may be due to SRECs. Factoring in SRECs, in Massachusetts each kWh generated is worth about $.215 (what we pay for electricity) PLUS about $.20-$.40 or so (that we get from SRECs for the first 10 years). So if the payback period is less than 10 years, it's like we are generating electricity worth about $.40-$.60/kWh.

I'm confused on your SREC comments. You say each kWh is worth $0.215 but you say this is factoring in SREC. Then you add a plus $0.20 to $0.40 for those same SREC -- something doesn't make sense.

And while SREC may be guaranteed for 10 years, I believe it's a market price and that number has gone to pot in other states.

Take it from someone who has solar affected by seasonal shade (I'm getting several hours affected by sun per day due to the sun being lower in the sky vs my May to Sept production), shade will effect your production and thus affect payback. I'm still going to have a minimum bill from SDGE this year (probably a true up around $100), but next year will be different due to the TOU rate changes (my best guess is that this years usage would be about a $400 to $500 true up next year, but this is still less than the estimated $3500 to $4000 without solar -- this gets worse after the five year TOU time period grandfathering rolls off).

I'm not in the absolute no camp, but you need to take a strong look at your ROI / payback taking a pessimistic view of what SREC contributes.

[Sunking]

I'm confused on your SREC comments. You say each kWh is worth $0.215 but you say this is factoring in SREC. Then you add a plus $0.20 to $0.40 for those same SREC -- something doesn't make sense.

And while SREC may be guaranteed for 10 years, I believe it's a market price and that number has gone to pot in other states.

Take it from someone who has solar affected by seasonal shade (I'm getting several hours affected by sun per day due to the sun being lower in the sky vs my May to Sept production), shade will effect your production and thus affect payback. I'm still going to have a minimum bill from SDGE this year (probably a true up around $100), but next year will be different due to the TOU rate changes (my best guess is that this years usage would be about a $400 to $500 true up next year, but this is still less than the estimated $3500 to $4000 without solar -- this gets worse after the five year TOU time period grandfathering rolls off).

I'm not in the absolute no camp, but you need to take a strong look at your ROI / payback taking a pessimistic view of what SREC contributes.

You are correct Sir and in lot of states the SREC credits are worthless pieces of paper. SREC was a scam cooked up to make the brokers rich like All Bore.

[rscott]

Those EV owners took the bait. It is now known EV produce more pollution than an ICE vehicle. What the population in the USA does not know, shush its a secret, is to make an EV especially the battery, plus the power used to generate electricity produces more CO2 emission than a large luxury ICE car produces in 10 years on the road. Once you factor in no EV battery can last 10 years is no contest.

I think you need to move this to the forum where DanS26 is talking about how government subsidies of solar are shameful.

If not, you might want to look at https://cleantechnica.com/2017/06/22...y-study-sucks/ regarding that study that you are quoting as fact ("it is now known"), or perhaps the 2015 report by the Union of Concerned Scientists at https://www.ucsusa.org/sites/default...ull-report.pdf .

Yes, lots of electricity is generated from fossil fuels. But as anyone here should know, there are alternatives (such as solar). And guess what? You can't upgrade the gas grid to use non-fossil fuels, but you can upgrade the electric grid to do so.

[rscott]

I'm confused on your SREC comments. You say each kWh is worth $0.215 but you say this is factoring in SREC. Then you add a plus $0.20 to $0.40 for those same SREC -- something doesn't make sense.

Sorry, I didn't phrase that well. Factoring in SRECs, it is $.40-$.60 or so, the $.215 is what we pay the electric company.

And while SREC may be guaranteed for 10 years, I believe it's a market price and that number has gone to pot in other states.

True. Massachusetts has an effective floor price, though (it varies by year), which I believe averages about $200/MWh over the next 10 years.