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Utilities Battle Homeowners Over Solar Power
HughPickens.com writes Diane Cardwell reports in the NYT that many utilities are trying desperately to stem the rise of solar power, either by reducing incentives, adding steep fees or effectively pushing home solar companies out of the market. The economic threat has electric companies on edge. Over all, demand for electricity is softening while home solar is rapidly spreading across the country. There are now about 600,000 installed systems, and the number is expected to reach 3.3 million by 2020, according to the Solar Energy Industries Association. In Hawaii, the current battle began in 2013, when Hawaiian Electric started barring installations of residential solar systems in certain areas. It was an abrupt move — a panicked one, critics say — made after the utility became alarmed by the technical and financial challenges of all those homes suddenly making their own electricity. "Hawaii is a postcard from the future," says Adam Browning, executive director of Vote Solar, a policy and advocacy group based in California.
But utilities say that solar-generated electricity flowing out of houses and into a power grid designed to carry it in the other direction has caused unanticipated voltage fluctuations that can overload circuits, burn lines and lead to brownouts or blackouts. "At every different moment, we have to make sure that the amount of power we generate is equal to the amount of energy being used, and if we don't keep that balance things go unstable," says Colton Ching, vice president for energy delivery at Hawaiian Electric, pointing to the illuminated graphs and diagrams tracking energy production from wind and solar farms, as well as coal-fueled generators in the utility's main control room. But the rooftop systems are "essentially invisible to us," says Ching, "because they sit behind a customer's meter and we don't have a means to directly measure them." The utility wants to cut roughly in half the amount it pays customers for solar electricity they send back to the grid. "Hawaii's case is not isolated," says Massoud Amin. "When we push year-on-year 30 to 40 percent growth in this market, with the number of installations doubling, quickly — every two years or so — there's going to be problems."
But utilities say that solar-generated electricity flowing out of houses and into a power grid designed to carry it in the other direction has caused unanticipated voltage fluctuations that can overload circuits, burn lines and lead to brownouts or blackouts. "At every different moment, we have to make sure that the amount of power we generate is equal to the amount of energy being used, and if we don't keep that balance things go unstable," says Colton Ching, vice president for energy delivery at Hawaiian Electric, pointing to the illuminated graphs and diagrams tracking energy production from wind and solar farms, as well as coal-fueled generators in the utility's main control room. But the rooftop systems are "essentially invisible to us," says Ching, "because they sit behind a customer's meter and we don't have a means to directly measure them." The utility wants to cut roughly in half the amount it pays customers for solar electricity they send back to the grid. "Hawaii's case is not isolated," says Massoud Amin. "When we push year-on-year 30 to 40 percent growth in this market, with the number of installations doubling, quickly — every two years or so — there's going to be problems."
The complaints that the rooftop systems are invisible to the power companies "because they sit behind a customer's meter and we don't have a means to directly measure them" can be addressed pretty easily with updated electric meters.
The power companies are all moving towards "smart meter" technologies anyway. Why not make sure they've put one in that can monitor the output of a PV solar (or even a wind turbine) installation while they're at it?
When I had my solar system installed, the power company had to switch out my meter. And even though we're one of the last remaining areas around here that doesn't yet use smart meters, they still upgraded me to a bi-directional meter so my power generation vs. usage can be tracked. So they're spending $'s on labor and hardware to mess with your meter each time a new solar system is put in. It's their short-sightedness if they don't put more useful equipment in place while they're doing that anyway!
And when it comes to solar, I think the output is fairly predictable too. The only real "fluctuations" you get with the output are based on the day's weather conditions. If you compare my panels to my friend who lives on the other side of town and has a PV solar installation, our daily power generation numbers are within 2-3KWh of each other, and the hourly rates on a graph look almost identical. The power company receives and has to sign off on a registration form stating you've installed a small power generation system and they're made aware of its exact size/maximum output at that time. So even with NO other metering capability, they'd be able to predict that in a certain part of the circuit, they now have someone who will add, at most, a specific amount of power back to the lines between the hours of 10AM and 2PM (when the panels produce the most power). It seems like this is data they should be able to work with.
There's something to this claim. The power electric companies traditionally have control over all inputs to the system. Home solar changes that.
Unfortunately, the power company is still expected to make sure that the power comes in at the right voltage and frequency. And with control on only part of the inputs, that's a lot harder. The fewer inputs they control, the harder...
Theoretically, you can design a control system that'll handle the problem. But, so far, noone has bothered to, because noone's had a need to. As solar becomes more common that'll change, and the problems will go away.
One part of the problem is NOT going to go away however - they have to pay to maintain the lines. Right now, that cost if covered by your electric bills. As the amount of electricity you draw from their generators goes down, they're going to reach the point of needing to charge you a flat fee just for the connection to the power lines, plus the usual fees for actually using their electricity.
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Batteries need to come down in cost before it makes sense to switch to an off-grid solution. I have a 1kW battery/solar system (not grid-tied) as an emergency power source and I have to replace the lead acid AGM batteries aver 5-7 years at a cost of $500 to $1000.
The only way to beat the utilities is to go completely off-grid, but that is too expensive at the moment.
"The other half of the country is lucky to have reliable electricity." - You're spot on with that assessment. Brownouts in the Philippines are a way of life. it is particularly bad in rural areas. Many of the condos in Manila boast of their own power supplies independent of government power. Like a lot of other things in the Philippines, rampant corruption and cronyism has ruined nearly every industry. Before cellphones took off there it would take literally years to get a land line phone installed and you would probably have to bribe someone at that. Now just about everyone has a cellphone and the coverage is actually pretty good. The technology literally leapfrogged the old technology and I believe the exact thing will happen with solar once the price of the panels comes down.
EE working for a utility here, and I agree with all of this. The utility I work for, and a lot of others, don't even generate any power, we just do transmission and distribution, i.e. "poles and wires". Solar still causes us headaches. Don't get me wrong, I love solar, and I want reduced fossil-fuel usage, but the issue really is more nuanced than the public perception of "the utility just doesn't want us making our own power so they can keep charging us money".
Most people seem to operate under the assumption that power distribution is a network, where it flows in any direction. On the transmission side, yes, this is true. For distribution, it's generally false, except in large cities. More common are radial feeds, where several circuits, also called feeders, come out of the substation, each one typically having multiple branches and serving a certain area. Think of it like an artery system. The main trunk of the feeder has larger size wires that can handle more current, the branches have smaller sizes, etc. It's designed for power flowing from the substation to the customers, and not vice versa. There are a number of issues that arise when this expectation is violated. As a few examples:
If the homeowner at the end of the branch puts in a large solar installation, the wires and distribution equipment may not be sized to handle the power he's producing.
The variability of generation and inability to measure it is definitely an obstacle. Let's say there's an area with 20MW of load, and 15MW is being provided by solar. The solar output is unpredictable, but to the utility, who probably only has real time metering at the substation, it just looks like 5MW of load, so they don't know that when the sun goes down or a storm passes through they're going to see a major load increase.
It's a safety issue. The utility does not, and absolutely never will, assume that a customer has a properly functioning transfer switch that prevents backfeed during outages, which can be hazardous to both linemen working to restore power. There are certainly safety precautions that linemen can take, but it's still a danger.
On the billing side, the utility still needs to maintain equipment to provide whatever class of service the homeowner has. They need to be able to provide, for example, 400 amps, even if the homeowner gets solar and winds up having a bill of $0 from the utility. The O&M costs for such customers wind up being effectively subsidized by people who don't have solar.
I like solar, and I'm not afraid of it putting me out of a job, at least in my lifetime. I think when battery technology is more mature, it could help alleviate a number of issues that currently exist. But the public perception that its conspiracy by big bad utility is just trying to stifle competition is untrue. I'm not going to say that anticompetitiveness could never be the motivation for a utility to fight the proliferation of solar, but from an engineer's perspective, there are real obstacles that exist that many people don't realize or appreciate.
There are already strict requirements that must be met in order to connect a solar system to the grid. The devices that do this have all sorts of requirements regarding what the power must look like regarding conditioning and interesting things like disconnection should power drop in order to prevent energizing an electrical line that a worker thinks is dead because he doesn't expect you to push power. Meters that "run backwards" are also used with grid-tie connections already.
As it stands today in our existing system if an electric producer has excess they sell it to OTHER grids tied to their system, it doesn't simply go to waste. On an island like Hawaii that may not be possible but on the mainland it certainly is and those connections also stretch into other countries like Canada.
In short - most all of your assumptions about how power is just being thrown willy-nilly onto the grid are incorrect and already accounted for. If you think an electric company is going to allow you to (legally) connect without having passed those standards you haven't done your research. Look up Grid-tie to learn more.
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Bullshit. Hawaii power was forced to do an ACTUAL study instead of pulling number out their ass like you. They have areas with 50% of the power solar and the study found they can handle it just fine.
The utilities should keep in mind here, they push back hard enough and the cost savings of going completely off-grid will eventually reach the point that people just unplug entirely. It's better to offer backup power than no power at all.