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You're Doing It All Wrong: Solar Panels Should Face West, Not South
HughPickens.com writes In the U.S., a new solar project is installed every 3.2 minutes and the number of cumulative installations now stands at more than 500,000. For years, homeowners who bought solar panels were advised to mount them on the roof facing south to capture the most solar energy over the course of the day. Now Matthew L. Wald writes in the NYT that panels should be pointed west so that peak power comes in the afternoon when the electricity is more valuable. In late afternoon, homeowners are more likely to watch TV, turn on the lights or run the dishwasher. Electricity prices are also higher at that period of peak demand. "The predominance of south-facing panels may reflect a severe misalignment in energy supply and demand," say the authors of the study, Barry Fischer and Ben Harack. Pointing panels to the west means that in the hour beginning at 5 p.m., they produce 55 percent of their peak output. But point them to the south to maximize total output, and when the electric grid needs it most, they are producing only 15 percent of peak.
While some solar panel owners are paid time-of-use rates and are compensated by the utility in proportion to prices on the wholesale electric grid, many panel owners cannot take advantage of the higher value of electricity at peak hours because they are paid a flat rate, so the payment system creates an incentive for the homeowner to do the wrong thing. The California Energy Commission recently announced a bonus of up to $500 for new installations that point west. "We are hoping to squeeze more energy out of the afternoon daylight hours when electricity demand is highest," says David Hochschild, lead commissioner for the agency's renewable energy division, which will be administering the program. "By encouraging west-facing solar systems, we can better match our renewable supply with energy demand."
hedge your bets and go 50/50 south and west. Maybe 50% southwest, 25% west, 25% south and setup a water wheel and perhaps an agrarian society.
Obviously the panels should be motorized so that they are always facing the most optimal direction. A system that moves the panels shouldn't add that much to the cost and will probably pay for itself very quickly with the extra energy collected.
Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
If you're offgrid and storing excess power in batteries then point in the direction of most efficiency.
If you're connected to a meter and can run it backwards then point in the direction of most efficiency.
If you're only producing half your own power and pay a flat rate for electricity then point in the direction of most efficiency.
There are only a few specific situations where an individual would benefit from aligning solar panels with their usage patterns instead of maximum efficiency.
My guess is the majority of homeowners don't fall in that category.
Unless you are going to rotate the house.
Priest: "Universe from nothing, no laws of physics, sped up time"+ huge discrepancies. Creationism? No. Big Bang Theory
Great. So once solar installations start producing more total power than is consumed during peak production hours we should consider intentionally reducing their total output in order to better align production with consumption. Until then total peak solar production is only a fraction of the total energy consumed at the time, so there's nothing to be gained by intentionally sabotaging your total energy production. At least not or the people installing solar panels.
But sure, if you're more concerned about the power-transmitting capacity of your grid infrastructure than actually producing as much power as possible for a given investment, by all means point your solar panels west. Should be useful for California and, umm, anywhere else is the power companies are allowed to play ridiculous profit-optimizing games at the expense of the citizenry. And you'll be doing your part to please both the solar panel and fossil fuel industries. Good job consumer, the corpoatocracy thanks you.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
The point is, while he may be a special little snowflake, so is everyone else. What TFA really says is "Those who run the electrical grid get the most out of solar panels that are pointed west in California, as this has them pointing directly at the sun during peak electrical grid demand." That's significantly different than "Solar panels should face west."
If you're off-grid, you'll do best with pointing to the optimal location (there are charts available for this -- it's rarely south OR west) and storing the energy harvested for use when you need it. If you're just pumping it into the local grid, optimizing for high demand periods makes more sense (and the charts aren't tuned for that [yet]). However, this assumes that the electrical service you're using allows you to contribute back to the grid, and has a variable pricing scheme. If they don't, what real incentive do you have to optimize your energy collection to when THEY need it most? You'd have more incentive to tune for peak efficiency and sell it back to them when you don't need it -- and then buy back at the same rate when you DO need it.
So this whole thing's kind of a non-issue. Of course, what works best, as long as you're generating a decent amount of electricity, is to just track the sun from sunrise to sunset, assuming you'll offset the costs of the sensors and motors.
The article overstates the difference in angle -- not due west, you mean adjust west of due South. If you are in the northern hemisphere, there is an optimal angle depending on latitude. If you want to shift to later in the day, that is Southwest. If you live in Australia, that would be Northwest.
If you are a home owner, You should have some on both south and west if possible. At my house, we have 43 panels of which 7 are east, 14 are west, and the rest are to the south. As such, we get a lot more electricity when needed, then the average home.
I prefer the "u" in honour as it seems to be missing these days.
I just purchased a solar panel system for our home, and I've been learning a lot about all of this stuff during the process.
The problem with the author's suggestion is that he's concerned about a problem that, by and large, we haven't quite come to yet. Solar adoption is still such a small percentage of the total number of electric consumers that the "saturation point" hasn't usually been reached yet. The entire "net metering" model for solar isn't really sustainable if you get more than a single digit percentage of homeowners in a given area going solar. I think that will hold true EVEN if you could convince all the new solar installations to use west-facing panels to time shift their power production hours.
Right now, practically everything about PV solar adoption centers around government regulations creating an "artificial" incentive for it. For example, in my home state of Maryland and a number of others, they have an SREC program in place (solar reclamation credits). How does it work? Basically, they made a rule that the state's utility companies have to obtain a certain percentage of their electricity generation via "Green" sources like wind or solar. If they fail to hit that target, they must purchase these SREC certificates in a sufficient quantity to offset it. (In reality, they're always going to pay for the SRECs rather than adopt more alternative energy generation themselves -- because for them, it's still the more cost-effective and sensible option. They don't want to spend a bunch on new infrastructure and land to place it on, just to meet those percentage targets.) For every megawatt of solar power your home solar panel setup produces, you earn an SREC which you can turn around and resell to the power company (directly, or via one of several auction web sites designed for the purpose). There's even one offering to buy 10 or 20 years' worth of your SRECs in advance, at some discounted price, giving you more "up front" cash to pay off your system's initial installation cost - should you find that the best option.
Don't forget the Federal tax credit of 30% of whatever you spent to buy the solar panel system, and states like mine who kick in another $1,000 or so. This stuff just doesn't make the same financial sense with all of these constructs removed from the equation.
The real elephant in the room that everyone's ignoring is the fact that power DISTRIBUTION is the limiting factor for the power companies. As soon as too many people start putting power from solar back onto the grid at one time, in one area? They can't really do anything with it, so it gets wasted. Yet the "net metering" rules require that pay you back for it anyway, at full retail prices. For a SHORT time, you might be able to postpone this by switching more panels to face west instead of south, but soon enough - it will become a problem again.
Honestly, I predict that what we'll see playing out is government withdrawing all of the tax breaks, followed by the value of your SRECs dropping to very little as they ease up on the requirements the utilities must meet. This will put the brakes on solar adoption, making it one of those things that only paid off for the people who got in on it early - or who have a situation where it STILL pays off (due to especially high power costs). In Hawaii or parts of California, for example, I believe the utilities sometimes bill as high as 90-some cents per kilowatt-hour used. In Maryland, by contrast? I pay closer to 11 cents.
The optimal position of solar panels depends on several factors:
Tracking mechanisms work, but they are mechanical and can fail, and they cost money. It may be cheaper to add panels than to add trackers. For seasonal adjustment, some mounting hardware allows relatively easy manual adjustment of the slope.You don't have to change this but a few times a year.
I have been off the grid at home for ten years, depending mostly on solar but with a little wind. Our panels are pointed in three directions: Southeast to get power in the early morning when the batteries are lowest, south for use during peak sun, and southwest to end the daylight hours with fully charged batteries. We have home-made mounting, and it was cheaper to add a few extra panels than to add tracking hardware.
You must live in a location without wind. A solar panel must be mounted such that it will not blow away in a 100 year wind (if you want it to survive with high probability over the 30 year panel life). This requires a very robust motorized mounting in most places. A very significant expense.
Starships were meant to fly, Hands up and touch the sky - Nicky Minaj
I'm installing solar neutrino panels, and facing them down. That way I can get power at night when I really need it.
a homeowner can buy a device called a tracker that will pivot them
For those of us up in Canada or Northern Europe you need to mount the pannels on a vehicle which heads a long way south or west trailing a cable if they are going to be pointing at the sun in the late afternoon since the sun sets here around 15:30-16:00 this time of year. Simply pivoting or pointing west is just not going to cut it.
Can't you mount them south facing with fish-eye lenses on them so that they get a good amount of the sunlight when it's coming from any direction?
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Thats exactly what we do, its an 'at will' watering system, meaning the animals have 24hr access. the system is faced primarily south, is on a float activated switch, and maintains the water level in the supply. The point is, more animals use the system during the hot part of the day, meaning the system has to run more to maintain the level. Obviously, this means facing the panels to deal with the mid day load, aka, South.
I've decided to Diversify my Holdings. I've divided my cash between my left and right pockets, instead of all in one.
Concentraters exist and are used. But a fish-eye lens is so far out of the range of economic it's just silly.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'