
UPDATE: I’ve answered questions from commenters below in the FAQs, and added additional diagrams – Anthony
Much to the chagrin of people who are sure I’m evil, in the pocket of big oil, and highly carbon positive, I’m actually an independent and pretty energy efficient guy, and I challenge any of my detractors to show their solar and energy efficiency projects. Put your money where your mouthpiece is, I say. For example, do loud climate campaigners Joe Romm and Bill McKibben have solar power on their homes? Do Jim Hansen and Michael Mann have solar power while telling us we all must cut back our energy usage linked to fossil fuels? Inquiring minds want to know.
Readers may recall last summer that I put up my third solar power project, my first being on my older home, then a large 125KW solar project I started as Trustee for the Chico Unified School District. My third project is doing quite well, and a number of readers have asked for an update on my original article as they are considering doing what I have done. This being the day of the electricity denying “Earth Hour”, I thought it would be a good day to write about how I’m beating my electric bill. You see, while many tout the supposed CO2 saving properties of solar panels, my impetus is entirely different: I’m hedging against California’s exorbitant green-driven utility rates.
For example, see below from my bill last year when temperatures went up in the summer, and tell me if where you live you come anywhere close to paying what I do.
Above: my actual rate and costs from last summer June-July 2012.
Thanks to PG&E’s new smart-meter system, they can now gouge me more efficiently and on schedule, when I need electricity to keep cool the most. I doubt there’s anyone reading this entry that pays 93 cents per kilowatt-hour to keep their home cool in summer.
I (along with millions of others in California) pay what I call a “location tax” due to my living in California’s Sacramento Valley, where summer temperatures regularly hit and exceed 100F. The majority of California’s population, living along the coast, don’t see temperatures anywhere near that, and thus don’t have similar air conditioning issues.
And, with the California Air Resources Board (CARB) running amok with cap-and-trade regulation frenzy, with refusal of coal and nuclear energy, relying on green wind power mostly for the future, combined with a looming national Carbon Tax, finding a way to generate your own electricity is in my opinion, the best hedge against future cost increases. Climate concerns don’t even rate with me on this issue, I’m thinking more about my financial future and the health and comfort of my family, and that’s why I got a solar system – it’s a hedge against the green energy and climate madness.
Here’s how I beat the green menace and PG&E.
Remember back in December when climate scientist Dr. Michael Mann was so out of touch that he couldn’t even conceive that I could do calendars for myself (I sent him a free one), but instead it must have been some nefariously funded production? Well, he probably can’t conceive of how I put up my own solar system either, since like the Josh Calendars, I did it using COSTCO and some sweat equity.
Here’s a few FAQs.
1. Did “big oil” or some other entity pay you to do this?
No.
Did you use government grants to do this? No. Did you get money from the WUWT tip jar or calendar sales to do this? No.
So how did you pay for this? Simple. I took out a low-interest loan against my savings account the contents of which was then converted to a certificate of deposit spanning five years. I’ll have the solar system paid for in five years, and the CD will be free at that time. Then I’ll have a solar system and my savings principal intact plus I’ll get interest on the certificate of deposit. Basically I’m trading my PG&E electric bill for a financing bill for five years.
How much did it cost? About $25,000 and change, fully installed, plus shipping and tax on the hardware portion.
2. Why didn’t you get one of those “no money down” solar systems being advertised today?
I’m borrowing and adapting a popular credit card slogan to best explain this: “ownership has its advantages”. I looked into several of these other plans, and when I penciled out the entire scheme, it didn’t make much financial sense, and at the end of the lease, I either had to buy the system at “fair market value” (to be determined) or they come and remove the system. And given the number of solar company bankruptcy/failures out there (think Solyndra), I was concerned that I’d be straddled with a system that was orphaned due to the company going out of business and the debt purchased by some holding company, who could then argue that previous contracts were “null and void” due to such bankruptcy and “oh, by the way here’s your new payment schedule”. When you want to control your own destiny, relying on others is not a safe bet.
3. Grid-tied or battery storage?
It is a grid-tied system. Battery storage systems really don’t make any sense for a city dweller, as they are primarily off-the-grid type applications where you need independent power 24/7. This was primarily a financial consideration, not a power security one.
4. Did you get any government rebates?
No, there was a PG&E rebate program, which put about $1200 (based on my system size) back in my pocket, but as I said earlier, I got no government money related to this. There will be some small tax advantages for me.
5. Does it make any noise or heat?
No, the inverters are essentially silent, except for one small fan. The inverters do make some waste heat, but they are mounted outside, and not an issue. The solar panels actually help keep the house a bit cooler, as they absorb sunlight for a good portion of the roof space, which otherwise would have gone to heating the attic.
6. Has it saved you money?
Yes, absolutely. More details follow.
7. How does your power bill work now?
We get a quarterly summary showing our electric use/surplus, and a year-end “true up” bill to balance any difference. We still have to pay for natural gas usage separately.
8. How big is it? How much power?
36 panels, of 250watts each, for a maximum DC output of 9000 watts (9KW). Of course that’s under optimal sun angle and atmospheric conditions, and with DC to AC power conversion loss, the real max is closer to 6500 watts of AC power. Typical days run anywhere from 4500-5500 KW at peak sun. I opted for the better monocrystalline (blue color) panels rather than the polymorphous (brownish) solar panels as they are more efficient and longer lasting.
9. (added) How soon do you expect to be able to pay back your investment?
If I assume a linear payback rate, it would be about 12 years. However, I think it will be closer to 9 years based on my estimates of what the future holds. First, a look at recent rates by state:
Source: http://www.pacificpower.net/about/rr/rpc.html
Now, look at the forecast for residential electricity prices. It isn’t linear.
Source: US Department of Energy
10. (added) What is your cost of capital?
The way my loan is setup, guaranteed against a certificate of deposit earning interest, the APR works out to 0.8%. Over 5 years, that works out to be $511.66 for the cost of the loan.
11. (added) How does the mounting system affect your roof integrity? Will you get leaks?
The installation was guaranteed to be leak free, and after this winter rains, I can testify to that. The way the roof mount works, the screws used to secure the rack support post are put under a metal “flashing” cone, and screwed in with a sealant applied to the screw threads. This guarantees that there’s no rain penetration because the flashing not only prevents the screws from getting rain in the first place, the flashing acts just like another shingle. Here’s a diagram I prepared showing how it works:
See a descriptive animation here: http://www.unirac.com/video/animations/solarmount-i/index.html
12. Why didn’t you go with larger panels (like the 300 watt panels of the same size).
Because the volume pricing COSTCO had arranged (at that time) did not offer that size. Adding my 2% COSTCO rebate combined with the lower overall cost made the 250watt panels a no-brainer.
Specs on the panels are here:
GRAPE SOLAR 250W MONO PDF
13. How was the system shipped?
It arrived by truck as two large pallets, plus a third long package of rails. I stored these in my garage, unpacked them, and hauled the shipping materials to my office dumpster.
14. What about possible hail damage?
The rated impact resistance: hail diameter of 28mm (1.1″) with speed of 86km/h. (53mph)
These panels are really tough. My installer says you can drop them from the roof onto the concrete and they’ll survive just fine (he’s done it by accident more than once). here is a video and a news item that suggests the panels are tougher than the roofing.
News item:
Surprisingly little damage to rooftop solar panels
The epic hailstorm did surprisingly little damage to the tens of thousands of pricey solar-power arrays built on metro Phoenix rooftops in recent years.
http://www.azcentral.com/business/articles/20110930biz-hailstorm1002solar.html
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Purchasing the system
As I mentioned, I used COSTCO to buy the entire hardware system. They resell from a company in Oregon called “Grape Solar“. Here’s their largest package:
I actually wanted more power than that, so I contacted Grape Solar directly, described my needs, showed my house roof plan and power bills, and they came up with a custom design for me at no charge. Here’s the line item summary of what I bought:
I did a lot of research on this system, and found it was well designed and likely to live up to its claims, 8 months in, so far so good.
NOTE: Detailed instructions on how to order your own system from COSTCO follow at the end of this article.
Here’s links to manuals (PDF) on the items above:
- Grid-tied Solar System Layout Example
- Solar System Install Guide
- Solar Panel Specification Sheet
- PV Power Inverter Manual
- Solar System Quickstart Guide
I particularly like the Kaco Blue Planet DC to AC PV inverters, which are compact, quiet, efficient, and good-looking to boot. Here they are (5000 watt and 3500 watt models) on the side of my home with the PG&E SmartMeter. DC power comes in at the conduit from the solar panels at top right, AC power exits at bottom left in the curved conduit to junction box to tie into my AC mains breaker box.
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Installing the solar system
While I “could” have done the entire installation myself, having mad electric and electronic skills, I opted to have someone experienced in this particular technology do it for me. The Grape Solar company contact gave me a list of certified installers in the area, and I called each of them up and asked them questions. The guy who held up under my intense questioning (A fellow in Redding named Baran Galocy) got the job. For some of the installers, I knew more than they did, never a good sign. Choose wisely.
Plus, this fellow was willing to work with me to trade some sweat equity for a lower installation cost. Since a good portion of time is spent in transport, unpacking, staging, and disposal of packaging, I opted to perform those tasks in sync with his job schedule to save labor time and thus money. Check with an installer you might choose to see if they will do the same for you.
Permits, of course are required. The first step was getting a city work permit, so that the city could get their “cut”. I say this because their inspection was total BS, the inspector never opened a panel box or climbed on the roof to inspect panels. He was most interested in whether mandated warning labels like this below (to protect the stupid) were properly applied. Your mileage in your city may vary. Fortunately the installer handled getting these, keeping my blood pressure down.
The next step was to put up the UNIRAC mounting system on the roof:
This took about three partial work days to complete, since only mad dogs and Englishmen work on rooftops in the midday summer sun. Here it is completed:
The next step was placing and securing panels, while doing base panel wiring:
Note the ladder contraption at the right. This is carpet remnants secured to ladder and rooftop. Shown in red to the left of the ladder is a nylon rope hawser with clips I designed that allows the man on top to pull up the panels while I push from below. This saves your back, plus virtually eliminates the possibility of dropping them and/or an injurious fall. The carpet prevents the panels from being scratched or damaged while they are pulled up.
This paneling operation took about two partial work days to complete.
Finally, the last step was to hang the inverters on the outside wall and to finish all the interconnect wiring. which took about another day.
Waiting for the city building inspector and for PG&E to “approve” the installation for grid connect took far longer than the actual installation. Then I discovered that PG&E changed one of their forms in the middle of the process, and we had to re-do the paperwork. While the install was competed in August, we didn’t actually get the final connect and switchover to net metering until December. Ain’t bureaucracy grand? I was just unlucky, you can figure about 2-4 weeks in most cases.
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Results!
Here is a photo of my SmartMeter running today at about 940AM:
The 5.01 kW reading is my instantaneous generation, note at the right side it says “Received”. If I am using more power than I generate (or it is nighttime) that will switch to say “Delivered”. So now as I’m writing this, I’m 5kW net positive at my home.
At the top, in the big numbers is the summation of Kilowatt-hours over the lifetime of the meter. When the meter is delivered, it is set to read 00000. If I am using more electricity than I generate, it will show a net positive value (i.e 00234) if I have generated more electricity than I used, it will go backwards from 99999 and as this shows I’m at 99340, leaving a surplus of 660 Kilowatt-hours since the system was switched over in December. most of December and January was fairly overcast here, so my biggest gains have been recent, as shown in my SmartMeter summary online (highlighted in Yellow), I’ve now surpassed energy-efficient homes in my area:
My usage has gone negative:
Nice to see the money flowing to me too, here’s my quarterly bill:
Unfortunately, I still have to pay all those taxes and fees amounting to $4.66, even though I’m a net generator rather than a consumer, but I’ll take the deal.
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How this works
The strategy is simple, generate/save as much electricity as you can during non-summer months, bank it (as shown on the meter) and then draw against that bank of generated energy during the summer or when you need power. Hopefully at the end of the true-up period, I’ll end up with surplus, in which case PG&E is now mandated by state law to send me a check. Amazingly, it didn’t used to be that way, and they were getting free surplus electricity.
If at the end of the true-up period, I used electricity, I pay for that then. Since I’m able to watch usage online and on the SmartMeter, it should be manageable to ensure we come out ahead (unless we have an extended heat wave). No matter what though, we are pretty much free of the tyranny of the 90 cents per kilowatt-hour in the summer when tiered rates kick in to punish us valley dwellers.
More info on the net metering program is here: http://www.pge.com/en/myhome/saveenergymoney/solarenergy/solarupgrade/index.page
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Do you want one for yourself? Here’s how you can help yourself and help me in the process.
Since I’ve done all the work of documenting the process, the Grape Solar Company has agreed to offer me a finders fee for anyone who purchases a similar system through them via COSTCO. Here’s how to do it:
1. Contact Steve Bouton or Garret Towne at Grape Solar via telephone or by email:
Grape Solar, Inc. 1305 South Bertelsen Road, Eugene, Oregon 97402
Tel: 541.349.9000 Fax: 541.343.9000
Email: steven.bouton “at” grapesolar.com or garret.towne “at” grapesolar.com
2. Tell them you read this article, give them my name so they will credit me.
3. Give them your details, they will design a system to suit your needs free of charge. They’ll need your address, description of your view of the sky to the south (sometimes visible on Google Earth) plus your goals for electricity saving, (full replacement, supplemental, add as you go, etc.). Arrange financing if need be – note how I used my local bank to finance a loan against my savings account for a win-win.
4. Grape Solar will set you up with a custom order you can place on COSTCO.com that will include everything you will need. Then contact an installer. They’ll also supply a list of installers in your area if you don’t wish to do the work yourself. As I mentioned, you may be able to do some work yourself to help the installer to save money. Be sure to ask.
5. You’ll make the order with COSTCO, either you’ll need a credit card with a high limit or you’ll have to wire the money to COSTCO (which is what I did). BE SURE TO ASK TO HAVE YOUR COSTCO MEMBERSHIP NUMBER APPLIED TO THE SALE. This will ensure that if you have an account that gives you a rebate for year total purchases, you’ll get that year-end 2% cash back. 2% of a $20K system is $400, well worth the effort!
6. You have your installer get work permits and do the paperwork with your local utility company – this is key. Without these being done right, you are dead in the water. make sure your installer will do these for you.
7. Install the system – get it inspected and turned on. Submit final paperwork to your local utility company for any rebate programs they may have.
8. Keep all your paperwork for tax time – you may be eligible for tax credits – check with your tax preparer.
9. Enjoy a lower or zero power bill
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I hope this gives everyone who is interested the path forward. if you have questions about this please ask in comments. – Anthony

















Roger Zimmerman says @ur momisugly March 24, 2013 at 8:01 am
I’m guessing this independence factor is the real win.
I agree with you;security is worth money.
Actually, you did clearly say in the FAQs what your payback period is and what the system cost in total. My mistake.
Today’s Google ad is for accepting credit cards.
The best ways to reduce eneergy consumption in a home is architectural; however, humidity in hot locales necessitates energyconsumtion. Before air conditioning was invented in Syracuse, New York, of all places, Florida was sparsely populated.
For a truly sustainable energy source, one need look no further than an engine that runs on nothing more than air and water – two very common materials.
What many do not realize is that the reaction 2N2 + 2H20 + 5O2 ==> 4HNO3 + energy.
In other words, you can burn the atmosphere and oceans and produce energy without the messy complications of fusion. The activation energy is quite high so it is still an engineering problem to make efficient, but in theory it will work. All that is required to make the process efficient is a suitable catalyst. The waste product might be a bit of a problem, but at least it won’t cause global warming.
You might want to consider shading the inverters. Keeping them cooler makes them last longer and raises efficiency.
Physics Major March 24, 2013 at 6:46 am also makes an excellent point. One I have made many times at my ECN column. http://www.ecnmag.com/tags/Blogs/M-Simon/
Tom in Florida: I do not see anyone addressing a couple of simple but important things one can easily do to lower their electric bills. First is the temperature setting you choose. I live in SW Florida and I set my summertime thermostat at 84F; my wintertime setting is 65F. You simply dress appropriately when at home. I also have ceiling fans in every room and I leave windows open at night and in the early morning.
I do as you do. I should add that even in the San Juaquin and Sacramento valleys you can save a lot of money on summer A/C if you ventilate your house by fans from 3am to 6am. However, I know people who use A/C instead in order to keep down the dust.
ferd berple: What many do not realize is that the reaction 2N2 + 2H20 + 5O2 ==> 4HNO3 + energy.
And HNO3 is good stuff, eh?
(Hint: Climate Change is not a reason)
Well, from a different perspective, it is THE reason. Only because those buffoons in Sacramento and Washington D.C. have interfered with the market will this ever pay for itself. It is the hysteria over (catastrophic anthropogenic) climate change that makes it worthwhile economically.
Regards,
Steamboat Jack (Jon Jewett’s evil twin)
93 cents per kw-hr????
Insanity.
I see no opportunity to install solar panels on the roof of my principal residence, even with subsidies which I hate since the roof is totally shaded in the summer season by trees around the house
On the other hand I have a summer house at the central NJ shore that has 100 % roof sun exposure. I’m wondering how robust the panels are under heavy wind conditions due to “near” Hurricanes such as Sandy and frequent NE storms. While I had no water intrusion during Sandy, I did have a flagpole blow down and some fencing leaning. Also many roofs did loose the shingles.
Are Solar panels covered by home insurance if damaged?
Would leakage a tiedown bolting be a concern after heavy winds.
What is the impact of salt carried in the atmosphere on the life and efficiency of the panels?
If these are not subject to property taxed as any other home improvement. NJ has a high Property tax. If not why not?
As I said before NJ is on the road to hel%, even though we now have a R Governor, since the legislature is very left leaning like California and constantly attempts to override his vetoes. I expect electricity costs will continue escalate especially as the greenies are forcing the shut down of at least on Nuclear reactor and forcing the power companies to purchase green electricity at exorbitant rates that causes everyone else’s rate to rise.
We may be forced to make decisions such as Anthony has made to survive a repressive government.
All this is a load of bull. Yes, some can save by installing solar. Here in Australia the savings are made by transferring the costs of running the electricity supply system ( all those costs that are independent of the cost of generating electricity and the losses bringing it to your home) on to those who depend totally on grid electricity. Systems have also be subsidised by up to $600 per megawatthour of electricial energy they will produce over 20 years. Those with solar pay less for the grid they rely on all the time. Few people living where grid power is available will choose to operate independently of the grid because they can parasitize it as Anthony Watts does.
The question Anthony should ask is what would happen if everyone, households and industry, took the same percentage of supply from their own generation while still relying on the grid that supplements their supply and into which thet sell their excess electricity.
Just another brand of elites talking to other elites with money while “those people” eat the left over cold stale cake.
“Top marginal rate”; the price charged for the last few kWH demanded past some determined ‘cutoff’ or delimiting value.
This isn’t ‘Kroger’ or Piggly-Wiggly pricing, think ‘income taxes’ with higher *marginal* rates affecting (being applied towards) that last million (not the first million) that you earned …
.
I can’t justify Solar, even though I’d love to. My total cost of electricity is averaging about $1400 a year, which means even if I eliminated the cost (and I can’t where I live, there is a fixed service cost built in), it would take me 11 years to make back $25,000.
I simply don’t use enough electricity to make it worthwhile. Although I could use a smaller system, since my worst month was 2 mw, or about 3kw/hour, and that was with a huge christmas light display that I have since reduced somewhat and modified with LED lights.
If I went Solar, it would be to store, along with a natural gas generator I can switch to propane, and a large propane tank. Then I will be self-sufficient for a long-haul collapse of the support systems.
The top marginal rate for production can be higher for a discrete ‘standby’ facility, e.g. a gas-fired turbine which sees only brief periods of use during a year (spending the rest of the time “off” but can be in service up and running in say 15 mins) *.
Think: Buying a new car that still requires insurance and plates and service (6mo/1yr etc. on oil changes and lube regardless of mileage as lubes are prone to age) BUT only gets used twice or 3 times a year *by you* when low-cost mass transit bus service isn’t available …
What’s your cost per mile in that case?
* The alternative is “shedding load” (cutting off customers) and/or rolling blackouts. AT SOME POINT when generation CANNOT meet load something has to be done, or the system can (and will!) collapse (generators trip and cease to generate!) Then it’s hell getting the WHOLE system back up and synchronized. References supplied upon request based on “complete blackouts” we’ve seen in the last 70 years with several big ones in just the last 15 yrs!).
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metamars says:
March 24, 2013 at 8:21 am
“I recently corresponded with Gerard Aitken IV, son of the brilliant inventor Alvin Marks. He expects there to be a prototype for Lumeloid out by the end of the year ”
If they manage to make a rectenna solutioin work such efficiencies of 85 % become possible.
Some other people try to build rectenna solutions for IR using nanotubes, with similar possible efficiencies.
http://www.sciencebuzz.org/blog/nanoantennas-change-heat-electricity
Asked and answered I believe, in the 19th (or last) exhibit (the document stating in the heading “Net Energy Metering Electric Statement”) holds the clue; note the item labelled “Distribution” with a corresponding value of “$3.71”.
Ostensibly this would be the charge for infrastructure to perform the function of “electricity distribution” (hence the term often being shortened simply to “distribution”; this would include poles and hardware e.g. transformers, wire, insulators and costs including maintenance personnel and required vehicles and trucks).
http://wattsupwiththat.files.wordpress.com/2013/03/home_solar_pge_bill_feb2013.jpg?w=640&h=382
.
Do you have any idea how the cost compares to upgrading the structure? Added roof insulation, triple glazed windows, extended eves for shade, more efficient mechanicals, adding wall insulation, etc.? I realize this wasn’t the point of the whole exercise but it seems to me that you could come close to those kinds of savings with careful passive renovations.
To Max Hugoson, “Being currently an unemployed (late 50′s) Engineer, I have a strategy plotted out to SURVIVE until Nov/Dec, when I must (really, if I don’t want to dive into a DEEP economic hole) sell my house, and move to much cheaper digs (probably a double wide in AZ). SO I have JUST ABOUT THE $ that Anthony is spending on his PV system TO SURVIVE ON”
Hi Max, if you’re still hanging around we’ve been getting snow and a lot of bitter cold wind down here south of Branson, Missouri. Our beautifully bloomed Jonquils (Easter Lilly) are drooping to the snow covered practically frozen ground.
Max, have you ever thought about being a freight relocation engineer? I mean, personally I used to work in a laboratory doing quality control and have survived and actually prospered in this living hell of dysfunctional government economic policy. Yes, it sucks as a career choice but it pays the bills. I have 1 1/2 million plus miles without any accident charged to my record. I do love the travel and experiencing the big picture of weather on this continent.
What I offer is to train you after graduating a school if you were to have a need for one. I have trained a few and treated them well.
I agree with this post. About 4 years ago I did a 20-year life cycle cost spreadsheet for PV solar as a power source for an electric car and nearly fell out of my chair: an ROI in a just a few years and the incredible future savings even factoring the costs of something like a Nissan Leaf. The key was replacing expensive gasoline (@ur momisugly $4/gal) with cheaper electricity for an e-car generated by PV (plus a lot of other hidden savings). Like the author I have grid-tie, net metering, but I don’t live in CA. I live in HI where, at the time of the calculation, the base kWh was $0.20 (it is now $0.30) because almost all HI’s electricity is generated by imported oil (and some Australian coal and waste burning). I purchased a 5-kW system from dmsolar.com and had it installed 3+ years ago, and a Nissan Leaf (2 yrs ago, I now want a Tesla S sedan!) and my calculations of 4 years ago are holding true: I end up each month with money in my pocket. Note that I said nothing about low emissions. It’s all about money: (a) money in my pocket and (b) reducing dependency of HI on foreign oil – Hawaii sends billions (yes, billions!) of dollars out of its economy to someone else (you hear that Alaska?), which means more cash in the local economy. That said 8 of my neighbors (with pool pumps that eat hundreds of dollars out of their monthly budgets) took a look at my calculations, let me do a calculation or two for them, and then immediately bought (or contracted) for PV systems that are bigger yet cheaper than mine — thank you China for falling panel prices (for better or worse)! I am of the opinion that the tax subsidy for PV should be reduced in some regions since the ROI is now competitive with other sources of electricity and will continue to be so. Also, electric cars should be assessed a “road use tax” at yearly registration to offset the loss of the road tax in the cost of a gallon of gas.
The true measure of the effectiveness of any electricity producing installation is capacity factor. While you may be saving on your electricity bill, is it really the most efficient and effective way to produce electricity. Have you been able to calculate your capacity factor yet?
Additionally, since you are running a commerical operation on your property will you be paying the appropriate property taxes and income taxes? And, certainly those income taxes are not on just the excess income you receive back, but on all of the electricity costs you have offset. Until you have figured these in, your analysis is woefully incomplete.
Willis Essenbach said:
“First, where you live there is only about 40% of the need for cooling that Anthony has in Chico. CDD in Madison (65°F base) is 568 degree-days/year, whereas in Chico there’s 1,391 cooling degree days per year. With your pitifully small cooling load, it’s no surprise your power use is low.
Second, you’re not paying gouging outrageous PGE-level prices for your power.
Since neither of those are the result of your actions, you might dial the crowing back a tad …”
My comparison to Anthony Watts situation was for a record-hot July in Madison to a July in Chico. That month had more cooling degree days in Madison than Chico.
I aircondition and dehumidify against that 568 deg-day/year load with about 900 kWHr yearly. Prorated to Chico, the demand would be 2250 kWHr. The peak demand would be well below where the 93 cents/kWHr cuts in. Estimating 23 cents/kWHr from PG&E at the reduced peak demand, the cost of A/C for a season would be about $500 against $25,000 for the panels or a 50-year payback.
Or, I could supply the reduced A/C load with a much smaller panel, say $10,000 worth, still a 20 year payback.
And I will not dial back my crowing as I am attempting to disseminate a solution to high electric rates with high A/C need, that helps in Madison and helps proportionately more in Chico. That solution is based on the thermal energy stored in a house, the A/C efficiency with ambient temps published by Carrier, and the psychometric charts for trade of ambient temp vs humidity for a level of comfort. That solution is low tech but much less capital expensive than solar panels.
Lisa Knobel,
I guess your view is that the city and the company just “forgot” to tell Anthony he’s a commercial operation?
Anthony,
you’re not becoming as independent as your bill suggests, I presume – and that should hold for a community as a whole, too.
Take Germany as an example to lay out the principle:
http://i171.photobucket.com/albums/u304/wflamme/StromverbrauchundWind_PV-Produktionrelativ_zps1bb789f6.png
Green is the load duration curve for Germany, blue is 10% wind power, orange is 4% photovoltaics production duration curves. There is no way to scale wind or photovoltaics up to match demand even if the hours of highest and lowest demand were to match the hours of highest and lowest production (which they don’t when presenting duration curves).
Apoxonbothyourhouses says:
March 23, 2013 at 2:37 pm
“Stephen Richards says:
March 23, 2013 at 12:26 pm
My biggest gripe about solar systems is that it is a method for making the poor poorer and the rich richer.”
This is disingenuous talk.
Nothing disengenuous at all. If you read on you will see.