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Switching To Solar Power – One Month Later
ThinSkin writes "After an interesting article on solar panel installation for the home, Loyd Case at ExtremeTech has written a follow-up after about a month of normal use. Posting an $11.34 electric bill (roughly 3% of previous months), Loyd shares his experiences using solar power and how it can be fun for the geek, with computer monitoring services and power generation data. Of course, solar power isn't all fun and games, given the amount of required maintenance — even unpredictable maintenance, like wiping off accumulated ash from fires in Northern California."
According to the article California will not allow homeowners to sell more power back into the grid than they are buying. He doesn't say why. I don't understand the reasoning for such a restriction, since the possibility of selling more than you buy would encourage wider adoption.
If 'the people' in Amendment 2 are 'the state' then Amendments 1, 2, 4, 9, and 10 benefit the state, not you.
This is actually quite striking. I worked on a solar/wind project last year and the solar panel we were using was an 80W rated panel (normally provides a little over 60W in full sunlight at these latitudes), but I never realized how much your eyes compensate for the variation in illumination levels. When it was cloudy in the winter, even when you could see perfectly well and thought it was rather bright outside, the solar panel was only pumping out about 2 or 3 watts.
The idea is that it tends to be windy and sunny alternately, which is somewhat true, so they market wind and solar as a good combo, but the fact is the amount you have to spend to get the same power from wind is way more than the equivalent amount for solar, and trust me there are lots of times when it was calm and overcast for weeks.
Still I think the most economical setup would be to find a way to reduce the hardware as much as possible. Let's say you have air conditioning for instance. Take a solar panel, use it to charge a single 12V auto battery, and then use a voltage sensitive relay to turn on a surplus 12V marine air conditioner. Basically the solar charges up the battery. When there's enough power in there, the air conditioner kicks on and runs for 15 minutes or so and drains the charge out of the battery. The sunnier it is, the more the air conditioner runs, and that means your central air (powered by the grid) runs less. The benefit is that you don't need to fuss with inverters and big battery packs.
"I have never let my schooling interfere with my education." - Mark Twain
Well a house in Calif* with a clear view of the sky & enough room for 27 solar panels is about $2 million. So it's a choice between saving $250 on electricity or saving $2 million on housing.
Mod parent up! I am posting from a house with four 80W solar panels on a rainy day and the generator is on. If you want to go solar you need a lot of batteries and a lot of panels.
Of course, we don't have the convenience of mains power at all.
F.Y.I
Current usage is; 1 laptop (80W), 1 low power fridge (120W), 1 one modem (8W). Storage is 4 deep cycle batteries.
Comment removed based on user account deletion
So he saved about $330/month. It cost him $36K (which really cost $50K, but let's say). So it'll take 109 months to get back the money, or 9 years, not adjusting for inflation and investment opportunity cost. Let's say that brings it up to 12 years. Not including maintenance and repairs. It might even need complete replacement at that point. At 50K, which is the real cost, we're talking more like 16-18 years.
It seems to me that could change rather dramatically if the price of electricity goes up. I wonder what effect his solar array will have if he buys an electric car that can be plugged in.
"I like to lick butts!" by MobileTatsu-NJG (#32700246) (Score:5, Informative)
$11.34 + this months payment on the loan covering the costs of installation + costs of maintenance and operation.
For some people it's not only about saving money but being a good environmental steward.
It sure will. Even in California or here in Florida you have fewer hours of sun in the winter. Since most people on solar are trying to live on far less energy than a human needs to be comfortable in order to utilize technology that simply isn't cost effective yet, I have no doubt they will be borrowing from the grid in winter.
Of course, if you'd RTFA, you'd know that the author mentioned that and figured his overall power bill to go from $4000 to roughly $1000 yearly.
You'd also have known that he states his power usage is higher than your typical family home due to the fact that both he and his wife work from home, he's got two teenage daughters, a pc lab, and pretty hdtv setups around his house. (thus the $4000/yr electric bill in the first place)
If you wanted to be a crotchety bitch, which clearly you did, you would have mentioned that it'll take him roughly 11-15 years to recoup his investment of $40,000 for the equipment and setup. That's what I'd go with.
You'll have that sometimes...
It's worse than that. The $11 bill was for 19 days, not a month. And 19 sunny summer days, at that. He won't save $330 per month. Let's see what the figures are after a whole year. My guess is that he'll save around $200, at most. For a $36k investment.
Seriously, if I had a $300+ monthly electricity bill, I would start by seeing how I could reduce the amount of electricity used.
Yea, I was shocked at how much energy the family in this article uses. My GF and I average ~370kWh/month, 4,440kWh/year. We live in Mountain View, which is the next small city over from Sunnyvale. The family in this article is using 17,400kWh/year. If he expects a 20% drop in usage when the family becomes 2 people, that's still THREE TIMES what we use. I also have a home server and network.
My monthly electricity bill is roughly $25 a month without any alternative electricity generation winter or summer. My wife and I just use less. For example, proper window shade use keeps the house at 70 degrees during 100 degree weather without the need for fans or AC. Most of my energy is sucked up by a small fridge and surfing slashdot and such. The point is, alternative energy is great, but learning how to live with less can go alot further. My town (pop. 15,000) has actually as a whole cut their electricity 20% since 1987 through vast socialized conservation efforts (better lights, better insulation, etc). Most locals walk or ride bikes, and our police station, city council, and fire station is 100 % local solar and wind energy. Yes, I live in America. PS, I'm not a luddite, I live quite comfortably, I just utilize the surrounding environment more efficiently than most.
Guys -- you all seem to be neglecting the recent developments in solar financing.
(Disclaimer -- I do work for SolarCity http://solarcity.com/, a leading installer of residential solar arrays in the SF Bay Area and beyond. I won't make a totally shameless plug here, I'm trying to be fair to the other good and clever solar companies out there. A rising tide lifts all boats!)
By bringing in a 3rd party commercial owner via an Operating Lease or Power Purchase Agreement (PPA) structure, the customer can save money from solar on Day 1.
The 3rd party (an investment fund, or perhaps the solar company themselves) owns the system and claim the full range of available incentives. As opposed to residential owners, commercial owners can take accelerated depreciation on the system, and can take the full 30% federal tax credit (rather than facing a $2k cap), and they also get whatever state/local/utility incentives are available as per usual. The customer has a low (or zero) down-payment, and makes monthly payments over a period of ~15-18 years. The tax investor receives a reasonable return on their investment over time, the installer makes reasonable margins on the installation, and the customers can save money from Day 1. Everybody wins!
So to use the parent submitter's house as an example of what we can do -- For a $300/month average bill in Sunnyvale, CA, we might recommend a 7kW DC system. Assuming the customer had decent credit (720 FICO), we would require no down payment, and then charge monthly lease payments of $181/mo, for 15 years. The monthly payments do go up at 3.5% per year (we could alternatively have 0% escalation, but of course that would require a higher starting payment and so it's harder to show savings right away... there are many possible variations here. Also remember that local PG&E utility rates are increasing at >5% per year on average).
With this 7kW system, they might expect their average monthly bill to go from $300 to $72 per month. Add the $181/month payment, and their new average monthly electricity cost is (181 + 72) = $153/month, for immediate savings of ~$47/mo!!
The installers offering these plans usually offer full service/maintenance for the life of the lease, including replacement of the DC/AC inverter if necessary.
The customer is given the opportunity to purchase the system after years 6/10/15, or if they have to move or sell their house. The panels are warranted by the manufacturers to last 25+ years, so a long-term buy-and-hold strategy is solid. Or, if the customer looks around in 15 years and sees a better/cheaper technology, or just doesn't wish to renew or buy out), they are free to end the lease and we'll remove the panels at our cost.
The customer who understands Net Present Value (NPV) calculations can easily demonstrate that this offers far superior savings compared to either a) doing nothing, or b) purchasing the system for cash.
So before you all roll your eyes about solar being a poor investment with a 12+ year paybacks, please consider such alternative financing approaches.
Very old panels (over 25 years) still produce a good amount of power. A lot are "retired" at 75% output and you used to be able to pick them up cheap.
She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
I put a 3kw system on my roof in February, 2005. (I live in Silicon Valley). My electricity bill has been zero since then -- well, actually, $60/yr in some fee PG&E charges. My total electricity cost for the previous three years (2002-2004) was $6,730. Installation of the solar panels cost a net of $13,369 after rebates. So I've saved 50% of the cost already, and my house is worth more due to the presence of the solar power array. I took advantage of California rebates which were higher then than now, though, so that's a bummer.
Window shade use keeps the house at 70 degrees during 100 degree weather without the need for fans or AC
Howzat? Even with no windows, no doors, great insulation, etc. I don't see how you can maintain a 30 degree temperature differential for more than a few hours.
The most rabid believers in American Exceptionalism are the exact same people whose policies are destroying it.
It isn't easy maintaining a beowulf clusters of generators, ya'know.
The CDC in Georgia agrees with you, generator operations is hard.
http://www.ajc.com/metro/content/metro/dekalb/stories/2008/07/12/cdc_power_outage.html
google "32 trillion offshore needs IRS attention"
Seriously, if I had a $300+ monthly electricity bill, I would start by seeing how I could reduce the amount of electricity used.
Exactly. By the sound of it, he has an active family. Thus, I suggest replacing any CRT/Plasma televisions with LCD versions. OLED would be better, but they're still a few years off. Replace all appliances with energy star ones. If you want to start moving out of the mainstream, there's further items. Like switching from electric heat to a heat pump system. Let's suppose he's on electric hot water and his family uses lots of hot water, and using less isn't an option. Well, there are a number of flavors of heat pump water heaters - from the desuperheater units on many heat pump systems to actual heat pump units that pull heat from the surrounding air. Or a solar water heater. Adding more insulation to the house.
Heck, I was just considering what would happen if you took a straight electric dryer and instead of just exhausting the hot air outside if you used a heatpump (think dehumidifier or window size AC unit) to move that heat(very efficiently) to the incoming air before using direct electric heat to warm it up. You'd probably need to add a line to a drain, and a pump to empty out the condensate, but most dryers are located next to washing machines, and they have a drain.
I don't read AC A human right
The other problem is simply the stock market itself. Getting 10% a year out of it might be possible over the long haul, but volatility in the time-frame of a decade could give you anywhere from -20% to +20% a year, or worse depending on what you are invested in. Plus if you have to take money out regularly then you have to take profits and you wind up paying a big chunk of those profits in taxes to the government and, depending on your income level, you can even push yourself into a different tax bracket. It isn't cut-and-dry.
On the flip side, it might be possible to take a tax credit for the money spent on the solar system, and if you can manage to spend the money up front it does in fact improve the value of your home and also significantly improves your monthly cash flow. Some people tend to burn their cash reserves regardless of what they think they've saved and burning it on something more worthwhile, like a solar system instead of a vacation, would definitely be an improvement. If you see the solar as a long-term investment then those improvements can, in fact, be more beneficial to you.
In any case, a standard California home does not need a 4KW system. 2KW will do just fine. I have a 2.5KW system and a fairly large house and if I didn't have 12 computers running 24x7 my electric bill would be nearly zero.
You get the most payback by cutting away the top tier electric rate. You hit diminishing returns if you cut away the entire electric bill. A 2KW system costs a lot less then a 4KW system. The best price point for a consumer inverter such as a Sunny Boy is 2.5KW.
I strongly recommend that anyone getting a solar system get it professionally installed. A solar panel system with a high voltage DC inverter setup (~400VDC, typically one or two strings hooked in series), grid-tie (no battery), requires zero maintainance.
Another thing people should consider, even before considering a PV system, is to get a solar water heating system. These don't use PV panels but instead convert sunlight directly into heat (pipes and glass basically). The efficiency is very good and the cost is far lower then a PV system, and will chop off a good chunk of the gas bill from your water heater.
My Solar System
-Matt
Yup, and the voting public seem to fall for it every single time. Either by not caring, or by caring yet not having the attention span to remember about it when they are in the polling booth.
Some have an even shorter attention and or memory span than that. It was government meddling that caused the health care problems to begin with. During WWII the US government passed price and wage control laws. Employers weren't allowed to offer employees more by law. However government saw how this harmed businesses so the let employers offer fringe benefits such as health insurance to their employees, and gave them tax breaks for doing it. Those tax breaks are still on the books so there is no free market in health care and insurance. If government gave those same tax breaks to people who bought their own insurance then you could have a freer market. If they wanted they could join a health care coop. Or buy private insurance. They'd be able to open a health savings account which they could then use to pay normal medical expenses while buying catastrophic coverage to pay catastrophic expenses like cancer.
Falcon
Should there be a Law?
I've yet to figure out why everybody doesn't have a whole-house flash water heater - the top-of-the-line model I have was about 4 bills on EBay. They heat water only when you need it, not all the time like standard water heaters. And I've got mine set where only half the burners operate when it comes on because the water I'd get if they were turned on fully would be so hot that it would be unusable.
My average gas bill 2 years ago before I installed my Bosch was almost $100 a month. Since I installed the thing, my bills are averaging about 1/5th of that - it finished paying for itself in January of this year. And I could take that bill down even farther (almost to zero) by installing a solar water heater.
No mod points, no meta-moderating/Firehose/all the other free work Slashdot wants me to do.
I would actually not recommend solar panels like the OP used, but rather look into solar-thermal generators.
Solar panels are only 15-18% efficient, and stationary ones only achieve peak output at high noon, so you need to cover most of your roof with them.
There are solar-thermal plans with a collector less than 6' in diameter (looks like a satellite dish) that follows the sun for peak output whenever the sun is out. They're more like 60% efficient, replacing 12x the area in solar panels. One 6' generator should put out 1500W, enough to power the typical household, and more can be added to power electric cars for example.
If everyone had one for their home and replaced their cars with electric cars and matching generators, greenhouse gas emissions would drop by 73%. If they were ever to be mass produced, the retail price should settle under $1000, even lower if they were subsidized. That is the most realistic solution to global warming I've seen.
War as we knew it was obsolete
Nothing could beat complete denial
- Emily Haines
Worse, in places where electricity isn't as expensive we're talking about 20 year paybacks. I'm paying ~.10/kWh for wind generated power (100% of the generation portion of the bill goes to an account to fund wind generation). This cost has generally been around around ~$100 a year extra for me to offset carbon output. I've got a good sized ~1800sqft house and we've been keeping it fairly comfortable this summer, 73F -- my last bill [just came today] was 1037 kWh for $115. Windsource was nearly net 0 cost due to how expensive natrual gas is right now.
I agree with some posters -- figuring out how to cut a few hundred kWh should have been priority number one. Sealing/insulating the house might have been in order, too.
It'd be nice to be off-grid, but I really can't justify it at these prices.
-- dieman - Scott Dier