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It is funny because we get cold called by these folks probably twice a year, and once a rep came up to our house and wanted to tell us about solar, so I gave th

It is funny because we get cold called by these folks probably twice a year, and once a rep came up to our house and wanted to tell us about solar, so I gave them a short tour of the 5KW system we installed 15 years ago. The one that has literally paid for itself (about half way through year 11) based on actual generation and power consumption statistics. It would have paid for itself sooner except that PG&E has twice updated the grid tie rules which have incrementally reduced the benefit of rooftop solar. The TPO systems as described are a boon to PG&E who, if you can believe their actions, is really concerned that people will just drop off the grid altogether.

skybrian 8y ago
Even without explicit subsidies, it seems like rooftop solar is still getting hidden subsidies? If homeowners were paid wholesale rates for the power they provide, with prices based on the spot market, would any of it make sense financially?
- vkou 8y ago
  No, it wouldn't. For the same reason that me operating a coal power plant in my backyard wouldn't provide me with cheaper electricity then just buying from the grid. A centralized utility, even a poorly run one, will always provide electricity safer, cheaper, and more consistently then thousands of tiny private installations.
  - labster 8y ago
    Counter example: PG&E. More expensive than smaller, greener alternatives. And 85 people killed just last year alone is the safety record.
    - vkou 8y ago
      PG&E provides ~100 TWh of electricity/per year. Rooftop solar kills ~1 person per 2 TWh of produced energy. Mostly from people falling off roofs. If you were to look at the big picture, and not one outlier year - and look at the entire past decade, PG&E will probably have a better safety record. Also, if you want to do fair accounting, you can't solely blame PG&E for California wildfires. The entire state is a powder keg - and they just happened to be the last people who touched it. It would have burned sooner, or later. If your horse bolts from a barn, because there is no barndoor, do you blame the last person who went into the barn? Sure. Are they the sole point of blame? No. Especially if your barn has a history of horses bolting from it.
  - ChuckMcM 8y ago
    I like this argument but I disagree with it. I will stipulate that PG&E qualifies as a 'poorly run, centralized utility' and based on its billing it cannot provide power to residential homes for less money than a locally installed solar system can. The reasons for this are worth considering. PG&E has to maintain a power transmission infrastructure. That infrastructure has a high inspection cost, land use cost, equipment costs, and insurance risk cost (witness that the threat of the being found liable that their transmission line maintenance (or lack thereof) contributed to the most expensive wild fire in CA history). Then there are the externalities which we don't account for as much in either scenario. Whether it is the cost of scrubbers on a coal plant, the waste storage costs of nuclear, or the gas pipeline infrastructure for natural gas plants that leaks methane into the air. What solar does it centralizes the manufacture of the energy production equipment with finite externalitie. It provides highly granular capacity that can be deployed without large step wise changes in capacity (this is the 'nearly unused plant' problem where you have to run a plant because the instantaneous need occasionally exceeds your current generate capacity while the average need is staying below that level (this is where Teslas battery farms help energy companies cut costs). So when comparing systems dollars to systems dollars, Solar with the current economics of about $3.25/watt installed is actually cheaper than poorly run centralized power plants.
    - vkou 8y ago
      Oh, don't get me wrong - solar power generation is fantastic in areas that can support it (Which is most of the world.) Rooftop solar power generation is what I have an issue with. Utility-scale solar has all the advantage that you cited, without the disadvantages of being incredibly labour-intensive, overcomplicating the electric grid, and offloading long-term maintenance to non-experts. If you are going 100% off-the grid, then yes, local installations may be cheaper (Because they don't include the cost of maintaining the grid.) However, you'll still have to maintain a national grid - because not all buildings or businesses have the rooftop capacity, or the hundreds of thousands of dollars in capital to install enormous battery blocks. So, what ends up happening, is that a few people drop off the system, and raise prices for everyone else - including people who don't have the option to drop off the grid. My building, for instance, houses 40 units. It has four times the rooftop capacity of an average home. No amount of battery storage is ever going to let it be grid-independent. Other residences dropping off the grid, completely, just shift costs around - they wont reduce overall costs.
  - Teknoman117 8y ago
    Define safer? more safe for an individual or more safe methods of generating power? Centralized utilities also have a nasty issue of not coping with natural disasters particularly well...
  - iainmerrick 8y ago
    A centralized utility, even a poorly run one, will always provide electricity safer, cheaper, and more consistently then thousands of tiny private installations. Not necessarily. For household solar, economies of scale kick in at the manufacturing level -- if you’re producing lots of standardized units, each household’s installation costs can go down. You’re right that there will be some distribution inefficiency, as some households will over-produce and some under. But it may not be that bad if most households size their installations sensibly. The centralized utility can balance distribution across many households, but there are some extra costs too -- installation and maintenance of power lines, power leakage, downtime due to faults. Edit to add: I suspect we could agree that district solar (small local utility companies) is an excellent compromise that gets most of the benefits of both types.
    - vkou 8y ago
      Maybe? A well-ran local utility is likely to do a better job then a poorly-ran large one. Unfortunately, how well a business runs is not always correlated with size.
  - ehnto 8y ago
    More efficient to produce a certain kW figure, but run for profit and at the cost of freedom for the consumer.
- ehnto 8y ago
  There are hundereds of different subsidies in the US across all the different states. Some vesting over time, valid from day x to day y, and all kinds of other scenarios. It's really complicated, but chances are high that there is a subsidy or grant somewhere you could take advantage of.
grogenaut 8y ago
Did they try and sell you anyway?
- ChuckMcM 8y ago
  Thankfully no. But they haven't seemed to have deleted my number from their phone number list either.
reaperducer 8y ago
PG&E who, if you can believe their actions, is really concerned that people will just drop off the grid altogether. It is. It just looks to the east where nearly all of the largest commercial energy consumers in Nevada have dumped NV Energy and built their own solar farms to save money.
MRD85 8y ago
How do you calculate savings at the 11-year mark? If you'd invested the same amount in index funds over an 11 year period you'd see your money double in an approximately 10 year period.
- ChuckMcM 8y ago
  We have kept records of the power we've consumed, the power we've generated, the cost of the system and the cost of repairs/maintenance (one panel and one inverter so far over its lifetime). For the financial analysis we assumed the money would be committed to paying for power one way or the other, there isn't really an option for putting it aside in the mutual fund so the 'invest' option was off the table. With the use of a current measuring system[1] we also have time of day usage numbers which is an option that helps people who aren't home during the day. In our case there is always someone in the house so the tiered rate metering was the only rate schedule we needed to consider[2]. With this information we can calculate the total money would would have spent just paying for power from PG&E and making no change, to the money we spent on the system install ($20,000) and the subsequent money we paid to PG&E for power and for their meter reading service. A bit more than 11 years after the install the total money spent over the period was less for the solar option. Our current annual electricity spend is about $420 (that is $120 for their meter reading + about $300 in additional KWh of energy above what we generate) vs roughly $3000/year or average $250 a month. Effectively $2600 a year is not being spent. If I were a min-maxer then I'd be putting that money into a mutual fund and it would start compounding and well, then the difference would start to look ridiculous. [1] "The Energy Detective" -- http://www.theenergydetective.com/ http://www.theenergydetective.com/ [2] While it is true we could have changed further things about our lifestyle to fit into other rate schedules that avenue wasn't pursued.
  - laurencerowe 8y ago
    It's worth modeling the cost of capital of your system to provide a fair comparison. Assuming the it lasts 20 years before you need to replace it entirely and after maintenance you save $2600 a year ($217/month) then what rate of interest could you pay if you took out a loan to cover the initial capital outlay? Plugging the figures into: https://smartasset.com/personal-loans/personal-loan-calculator https://smartasset.com/personal-loans/personal-loan-calculat... and adjusting the interest rate slider you get a monthly payment of $217 when the interest rate is 11.75%. That's a pretty good rate of return for your investment. Not ridiculous, but solid.

skybrian 8y ago

Even without explicit subsidies, it seems like rooftop solar is still getting hidden subsidies? If homeowners were paid wholesale rates for the power they provide, with prices based on the spot market, would any of it make sense financially?

vkou 8y ago
No, it wouldn't. For the same reason that me operating a coal power plant in my backyard wouldn't provide me with cheaper electricity then just buying from the grid. A centralized utility, even a poorly run one, will always provide electricity safer, cheaper, and more consistently then thousands of tiny private installations.
- labster 8y ago
  Counter example: PG&E. More expensive than smaller, greener alternatives. And 85 people killed just last year alone is the safety record.
  - vkou 8y ago
    PG&E provides ~100 TWh of electricity/per year. Rooftop solar kills ~1 person per 2 TWh of produced energy. Mostly from people falling off roofs. If you were to look at the big picture, and not one outlier year - and look at the entire past decade, PG&E will probably have a better safety record. Also, if you want to do fair accounting, you can't solely blame PG&E for California wildfires. The entire state is a powder keg - and they just happened to be the last people who touched it. It would have burned sooner, or later. If your horse bolts from a barn, because there is no barndoor, do you blame the last person who went into the barn? Sure. Are they the sole point of blame? No. Especially if your barn has a history of horses bolting from it.
- ChuckMcM 8y ago
  I like this argument but I disagree with it. I will stipulate that PG&E qualifies as a 'poorly run, centralized utility' and based on its billing it cannot provide power to residential homes for less money than a locally installed solar system can. The reasons for this are worth considering. PG&E has to maintain a power transmission infrastructure. That infrastructure has a high inspection cost, land use cost, equipment costs, and insurance risk cost (witness that the threat of the being found liable that their transmission line maintenance (or lack thereof) contributed to the most expensive wild fire in CA history). Then there are the externalities which we don't account for as much in either scenario. Whether it is the cost of scrubbers on a coal plant, the waste storage costs of nuclear, or the gas pipeline infrastructure for natural gas plants that leaks methane into the air. What solar does it centralizes the manufacture of the energy production equipment with finite externalitie. It provides highly granular capacity that can be deployed without large step wise changes in capacity (this is the 'nearly unused plant' problem where you have to run a plant because the instantaneous need occasionally exceeds your current generate capacity while the average need is staying below that level (this is where Teslas battery farms help energy companies cut costs). So when comparing systems dollars to systems dollars, Solar with the current economics of about $3.25/watt installed is actually cheaper than poorly run centralized power plants.
  - vkou 8y ago
    Oh, don't get me wrong - solar power generation is fantastic in areas that can support it (Which is most of the world.) Rooftop solar power generation is what I have an issue with. Utility-scale solar has all the advantage that you cited, without the disadvantages of being incredibly labour-intensive, overcomplicating the electric grid, and offloading long-term maintenance to non-experts. If you are going 100% off-the grid, then yes, local installations may be cheaper (Because they don't include the cost of maintaining the grid.) However, you'll still have to maintain a national grid - because not all buildings or businesses have the rooftop capacity, or the hundreds of thousands of dollars in capital to install enormous battery blocks. So, what ends up happening, is that a few people drop off the system, and raise prices for everyone else - including people who don't have the option to drop off the grid. My building, for instance, houses 40 units. It has four times the rooftop capacity of an average home. No amount of battery storage is ever going to let it be grid-independent. Other residences dropping off the grid, completely, just shift costs around - they wont reduce overall costs.
- Teknoman117 8y ago
  Define safer? more safe for an individual or more safe methods of generating power? Centralized utilities also have a nasty issue of not coping with natural disasters particularly well...
- iainmerrick 8y ago
  A centralized utility, even a poorly run one, will always provide electricity safer, cheaper, and more consistently then thousands of tiny private installations. Not necessarily. For household solar, economies of scale kick in at the manufacturing level -- if you’re producing lots of standardized units, each household’s installation costs can go down. You’re right that there will be some distribution inefficiency, as some households will over-produce and some under. But it may not be that bad if most households size their installations sensibly. The centralized utility can balance distribution across many households, but there are some extra costs too -- installation and maintenance of power lines, power leakage, downtime due to faults. Edit to add: I suspect we could agree that district solar (small local utility companies) is an excellent compromise that gets most of the benefits of both types.
  - vkou 8y ago
    Maybe? A well-ran local utility is likely to do a better job then a poorly-ran large one. Unfortunately, how well a business runs is not always correlated with size.
- ehnto 8y ago
  More efficient to produce a certain kW figure, but run for profit and at the cost of freedom for the consumer.
ehnto 8y ago
There are hundereds of different subsidies in the US across all the different states. Some vesting over time, valid from day x to day y, and all kinds of other scenarios. It's really complicated, but chances are high that there is a subsidy or grant somewhere you could take advantage of.

grogenaut 8y ago

Did they try and sell you anyway?

ChuckMcM 8y ago
Thankfully no. But they haven't seemed to have deleted my number from their phone number list either.

reaperducer 8y ago

PG&E who, if you can believe their actions, is really concerned that people will just drop off the grid altogether. It is. It just looks to the east where nearly all of the largest commercial energy consumers in Nevada have dumped NV Energy and built their own solar farms to save money.

MRD85 8y ago

How do you calculate savings at the 11-year mark? If you'd invested the same amount in index funds over an 11 year period you'd see your money double in an approximately 10 year period.

ChuckMcM 8y ago
We have kept records of the power we've consumed, the power we've generated, the cost of the system and the cost of repairs/maintenance (one panel and one inverter so far over its lifetime). For the financial analysis we assumed the money would be committed to paying for power one way or the other, there isn't really an option for putting it aside in the mutual fund so the 'invest' option was off the table. With the use of a current measuring system[1] we also have time of day usage numbers which is an option that helps people who aren't home during the day. In our case there is always someone in the house so the tiered rate metering was the only rate schedule we needed to consider[2]. With this information we can calculate the total money would would have spent just paying for power from PG&E and making no change, to the money we spent on the system install ($20,000) and the subsequent money we paid to PG&E for power and for their meter reading service. A bit more than 11 years after the install the total money spent over the period was less for the solar option. Our current annual electricity spend is about $420 (that is $120 for their meter reading + about $300 in additional KWh of energy above what we generate) vs roughly $3000/year or average $250 a month. Effectively $2600 a year is not being spent. If I were a min-maxer then I'd be putting that money into a mutual fund and it would start compounding and well, then the difference would start to look ridiculous. [1] "The Energy Detective" -- http://www.theenergydetective.com/ http://www.theenergydetective.com/ [2] While it is true we could have changed further things about our lifestyle to fit into other rate schedules that avenue wasn't pursued.
- laurencerowe 8y ago
  It's worth modeling the cost of capital of your system to provide a fair comparison. Assuming the it lasts 20 years before you need to replace it entirely and after maintenance you save $2600 a year ($217/month) then what rate of interest could you pay if you took out a loan to cover the initial capital outlay? Plugging the figures into: https://smartasset.com/personal-loans/personal-loan-calculator https://smartasset.com/personal-loans/personal-loan-calculat... and adjusting the interest rate slider you get a monthly payment of $217 when the interest rate is 11.75%. That's a pretty good rate of return for your investment. Not ridiculous, but solid.