My solar is something of a disappointment. I argued about ground placement to get southern exposure and was told it would be difficult and it wasn’t really an issue. I should have argued harder and spent the extra money. With western exposure and the sun low in the sky wintertime production is insufficient to fully offset the connection fee plus one refrigerator; that’s literally all that’s been running. I still get a $15 a month bill. I thought I might accumulate some credit in the winter when the heat pump isn’t running but no. So in summer with that pump running 24/7 and temps often reaching triple digits my bill is $35, which is minimal, but there’s only $20 worth of difference when I’m running almost nothing at all.
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How many panels did you get?
yes, everyone is watching the NEM 3.0 decision with great interest.
since we are late to home ownership, we can’t get solar panels fast enough to get grandfathered in, but as a member of the “have-nots”, I am a fan of 3.0. the cost of distibuted solar to the utility is high, and that get spread out to all of the poors who can’t afford solar. its same as the urban centers paying for the wildfires in the rural areas. totally not fair.
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It’s either 3 or 4. It’s a 2.7 kilowatt system for a small, 800 sq ft home I don’t spend much time at, maybe 4 days a month on average. I only put up solar when I realized it wasn’t practical to turn off the AC completely when I wasn’t there.
If I’d planned to go with solar from the outset I would have faced the roof south. But optimum positioning to avoid excessive energy costs is of course the worst positioning for using solar to offset those costs.
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2.7kW… so does it generate 15 kWh a day? (2.7 * 8 = 15)
That’s an impressive number. Around here, 15 kWh would be worth $5. Each day.
Something seems off. Typically, each panel produces 300W. 4 could only do 1.2kWh in that case.
I have 40 panels on one of my rentals, and they generate 15 kWh a day. The system is from 2006 with new inverters in ~2018. I relocated the panels from the roof to a separate place, mainly to protect the roof.
Does the arithmetic for solar panel installation work out financially for people who have installed one?
People who spend $20k-$25K net(I’m assuming that is the cost on average), what were they paying in electricity costs monthly on average? Also, I understand the life of solar panels are 25-30 years before they need replacement?
The inverters last much less, maybe 10 to 15 years.
I replaced mine myself, 2 units for $1200 each.
My system generates about $5 a day, maybe 240 days a year. Maybe $2.50 in the darker months. $1500 a year with current cost of electricity.
Replacing those 2 inverters for $1200 each was a no brainer (they died in different years, so it was a $1200 decision only each time).
I don’t think that the panels last 25 years only, but they degrade somewhat.
Keep in mind that when a company quotes you $25k for an installation, the hardware is maybe $8k to $10k. I replaced 2 inverters, all new wiring and new conduit and rebuilt the rack in a new location. I know what I spent.
My 40 panel system cost over 30k, which would take 20 years to recover. The system is 15 years old now.
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Great job @ptiemann
Labor costs definitely changes the equation it seems.
I wish I was as hands on as you though!
Could you explain this? Is roof not a good place assuming one has other space to do the same? Is the roof damaged?
IMO, solar panels are much cheaper now than 15 years ago. I put 3.7kw in 2015. Total cost was ~$9500 (after tax credits). The system has been generating approx 5700 kWh a year. Since PGE costs are high during the day, you can put a cost to that 5700kwh per year. If I put 25 cents per kWh, then it generates electricity worth around $1500 per year.
Over the last 6 years, panels have gotten more efficient. So for the same per watt cost, you get more electricity.
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the advantage of roof installation is that it typically already is sloped. The optimal slope is not 45 degree but 60 degree; this is a function of our geographical location (latitude).
If your roof is low-slope, you will lost some performance.
My building unfortunately has a flat roof. So a rack with the “perfect tilt” was installed (all by the previous owner). The rack is bolted into the roof. A risk of water intrusion. Water never intruded though, AFAIK
BTW, I build a small projects with 4 houses in 2015, 2 of them got solar panels from SolarCity. One of those 2 had a roof leak on the south facing side, presumably from those panels.
If you install the panels somewhere else, e.g. over a carport, you may be able to select a better angle and tilt for perfect south facing exposure, and a roof leak in a car port is better than above human occupied space.
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I think you are wrong about slope. I got good performance from a 6:12 roof. About 25% slope
It would likely work for my parents. They keep the temperature at 76 degrees in the winter, run the A/C in the summer and are in tier 4. IIRC their bill is round $300-$400+ every month even in the summer.
And I still can’t convince them to do it 
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The report is 200+ pages. Yes I need a summary too 
https://docs.cpuc.ca.gov/PublishedDocs/Efile/G000/M430/K903/430903088.PDF
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Looks like 4 from a distance but I re-checked the invoice and actually there’s 8 up there.
I get 0.05 a kWh for what I generate and get charged 0.11 for what I need from the utility. Connection fees plus various taxes come to around $25 a month. With the sun low in the sky my east/west sloping roof generates less than 300 kWh a month in winter even with clear days. So that’s $15 worth of credit against $30 worth of taxes and fees plus a small amount of usage.
Here’s my first bill. It’s off a bit as the solar wasn’t running for the first few days of the billing period. I was surprised that half of my electricity was purchased given my production. The heat pump plus minor things like the fridge run somewhat at night but still.
In any event the fact that metering isn’t net-net and I get paid only about half as much for what I generate as what I receive I’ve calculated my return on this system, including depreciation of things like inverters and the panels themselves, at about 2.8% a year double tax free and indexed to the cost of energy. As a component of my cash allocation, compared with bank deposits or municipal bonds, it makes sense. But it’s certainly not an "investment. Ignore the credit, the result of a refund of the deposit when I got hooked up, and just look at current charges.
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So, I haven’t read it entirely but the high level summary:
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Net billing - basically less money than net metering. Instead of guaranteeing $x/kw, the new net billing would align with the current value of power. Meaning, when there is a TON of solar producing in the middle of the day, then the solar panels would get less $/kw vs later in the day when there is less. this is meant to a) reduce the duck curve, (the fall of production when the sun starts to set) and b) incentivize storage to come in and give energy back or reduce demand at the peak 4-8pm time period, since that is when businesses are still open but residental demand starts lighting up as people get home from schools and work. supposedly, if low income people do solar, they get a better net billing rate to encourage low income adoption of solar
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include a monthly charge for using the grid - think of this as a toll for power lines. When you put power BACK on to the grid, making it 2 way, it stresses out the grid components than what they were originally designed for, which is 1 way power. so it shortens their life, increases O&M which all of us have to pay for, but since homes with solar aren’t using as much of the utility’s power, they pay less, which is unfair, and then the cost burden is distributed more on people who don’t have rooftop solar. so this is an attempt to make things fair (I don’t have rooftop solar as I am a poor who just bought a house this year and didn’t get to doing solar this year).
the other issue with solar owners is that they still want electricity when the solar panels stop producing, but just buy it at the most expensive time, but overall their bill is less, so they are effectively paying less but for the same service expectations as someone who doesn’t have solar. so this is to help make that more even.
I am a fan of this. this will push people to either install storage or soak up the extra energy in their EV and then put it back on the grid when it is most needed (4-8pm). CA is expecting a 5GW SHORTFALL for 2022, yet we PAID AZ to take our extra solar this year. in the next couple of years, AZ and NV will have enough solar of their own to deal with that they can’t take ours, even if we pay them a lot of $$. So this is an attempt to solve that issue too.
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