Green Power Claims
Green Power Claims
(OP)
When will we get to the point of truth about renewable energy? I read in the local newspaper last weekend that a Biomass plant in Wisconsin costing $250,000,000 will produce 55MW and supply "electricity" for 40,000 "typical" homes. Ok, that's 1375 watts each. The same paper published that a local wind project would produce 165MW and supply electricity for 45,000 homes. The vast number of readers are no doubt ignorant of these riduclous claims. I write to the author of these stories in the paper whenever he writes them but I think we need a national standard, possibly developed by IEEE to set a basis for measuring the energy conversion value of these projects. Otherwise, it's all snake oil. And intelligent decisions can't be made.
Why would anyone invest in wind when biomass electricity supplies 3 times as many homes per MW!
Why would anyone invest in wind when biomass electricity supplies 3 times as many homes per MW!
Neil





RE: Green Power Claims
Biomass 55MW/40000hm = 1375 W/hm
Wind 165MW/45000hm = 4125 W/hm
Frankly, all I see is a possible difference in how they define the amount of power used per home, and both numbers are technically correct for different reasons. 1375 W/hm is roughly consistent with average usage, while 4125 W/hm is roughly consistent with peak usage.
As to why a newspaper might mix the units, is that really that surprising?
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RE: Green Power Claims
The biomass will be running about 100% of the time at its rated 55MW or (55*24*365) = 480,000 mw-hrs/year
The wind will only run at peak output about 40% of the time, so (165 * 24 *265 * .40) = 540,000 mw-hr/year
The same type formula must be used for solar panel. At best you'll only see about 25% of a solar panels output over the year. A 3KW array will only make 6570 kw-hrs. That only $800 per year in savings for a home unit. For power sold wholesale or the avoided cost, its only $250/year. That 3KW system will cost $10,000 after rebates.
I point out the dolars so you can see the big picture. That biomass plant will save about $19,000,000 per year. The operating expense will be in the $4,000,000 per year range. Transportation of fuel (biomass) will reduce annual revenues to the $10,000,000/year range. That means it will take 25 years before the plant breaks even, not including the time value of money.
RE: Green Power Claims
Utilites will install a 25KVA transformer to serve a 3 homes in a subdivision. or a 10kva for a rural site with one home.
Neil
RE: Green Power Claims
AA batteries supply electricity, albeit DC, to millions of homes. Newspapers are a money making business (or try to be) so I don't get surprised when some weasel-wording is enocuntered. They have to sell advertisements and kiss whatever fundaments that can insure their survival. By the same logic, solar power is already heating millions of homes, without the cost and inconvenience of power plants or pollution.
Does that sound squirrelish? I read in a newspaper how one State (Arizona I think) decided that since the Sun provides so much energy that is used, the State has already met its renewable energy goals without the mess of power plants, investment or pollution.
RE: Green Power Claims
My usage is currently running ~900 kWh/month = 1232 W average usage. Usage will vary up to ±80% over the course of the year, depending on how AC-dependent the household is.
Peak power is on the order of 5 kW, since that's the largest solar panel system that RecSolar sells.
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RE: Green Power Claims
Its a pretty easy number to "home" in on, if you check the average power consumption statistics of homes on a regional or, in some cases, a national scale and for a yearly average. There can be considerable variation in richer vs poorer regions, and between winter and summer usage, but as an "average" number over a year 1375 is reasonable and relatively easy to verify.
RE: Green Power Claims
RE: Green Power Claims
I get your point.
But don't you agree that the statement in the paper that the plant "will provide electricity to 40,000 homes". implies all of their electricity? Remember the paper is written for the mass of people who do not have a technical background. And as someone else said, you might as well say the plant provides electricity for every home in the country. Afterall it is a unified grid.
I just want the average Joe out there to realize what the true scope of the project is.
I think it would also to be good to get into the fuel delivery issuer. Semi trucks delivery the fuel are going to give a lot more CO2 emission per joule delivered than the train delivering coal. Or the pile line of gas.
Neil
RE: Green Power Claims
RE: Green Power Claims
In either case, the ""will provide electricity to 40,000 homes" phrase is pretty much moot, since it's not really an actionable piece of information. Even the ostensibly accurate "55MW" and "165MW" numbers don't tell you bupkis about their steady-state output, their surge output, etc.
As indicated by another poster above, each technology has different strengths and weaknesses, which are not even touched upon in the article, so why is the number of home supplied such a big deal?
If you want a full engineering and scientific analysis, including ancillary factors, a newspaper is not the place to get it, not would I want it there, since it would bore the average reader to tears, given that they can't understand a tenth of the science behind the analysis.
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RE: Green Power Claims
I disagree with your 1/10 th figure. Left out a zero I presume
RE: Green Power Claims
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RE: Green Power Claims
RE: Green Power Claims
In other words, If we didn't know anything we'd be a lot happier. Particularly about paying riduclous prices since we'd be confident the result would be a much improved environment.
Neil
RE: Green Power Claims
While some would take that as an argument for finding more of our own oil, the likelihood of finding sufficient reserves is pretty low. Even if we find every drop we think exists within our national boundaries, at our consumption rate, we'd exhaust our own reserves in 13.7 yrs. And that's assuming that we'd have access to all that oil at reasonable prices. It's been clearly demonstrated that even US oil companies will sell to the highest bidder, and we therefore do not technically have secure supplies, even within our own national boundaries. And our so-called allies in OPEC are merrily gouging us and laughing all the way to the bank.
So, it just seems prudent to look at alternatives. I think there are sufficient reasons to do this, even ignoring the environmental part of it.
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RE: Green Power Claims
Neil
RE: Green Power Claims
No doubt every media outlet has its own agenda, but the news sources, i.e., the cartels, companies, lobbyists, and NGOs, are the real manipulators of perceived reality.
Even at that, the complexity of doing a "real" comparison of alternatives is non-trivial, since a "real" comparison would need to include ALL the relevant factors, and the analysis alone would be a huge money sink. Particularly since no one is willing to agree on where to draw the line for a strictly consistent comparison.
Nonetheless, the reason there are no good alternatives is because there are no good alternatives. A thread in another forum here drives the point home in that the OP is looking for an alternative energy storage, and the "best" solution is still batteries. Oil is indeed an magical elixir with its superior energy density and relatively simple conversion to electricity. A really good battery might have something like 1/10th the energy density of oil. If there was something that was even close, ala dilithium crystals, or whatever, there's be no arguing it.
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RE: Green Power Claims
Alan
"The engineer's first problem in any design situation is to discover what the problem really is." Unk.
RE: Green Power Claims
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RE: Green Power Claims
I think it would be a whole lot better to start telling them how much they would have to pay for that amount of electricity, if it all went through their meter in one month.
RE: Green Power Claims
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RE: Green Power Claims
I am curious about the rate structure though. Could you post it? or link to it. Here we have the possibility to choose day or night. Currently 0.13 Eu/kWh 10am-10pm day and 0.06 at night, or you can select one rate (near average) for 24 hours.
Day_night and One_rate. The Day_night options requires meter replacement.
I'm going to check into getting another line/meter and running the pumps on the One_rate during the day, then switching to the Day_night meter at night, but something tells me that that would be impossible.
RE: Green Power Claims
http://www.sce.com/newbill/residential3.htm
Here's a simplified version of the tiers:
http:/
Business rates are further divided into usage classes:
http://www.sce.com/CustomerService/rates/business/
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RE: Green Power Claims
And the things we do to avoid taxes. And what you will be doing to avoid utility rates.
I do understand the meter charge, and the cost of electricty, and demand (Flat fee, cost of fuel, and cost of equipment). But why must we make it so difficult with all the additional schemes, and rates?
RE: Green Power Claims
RE: Green Power Claims
RE: Green Power Claims
As for full-blown electric cars, nary a one. I'm not sure where you're getting your statistics, but there are nearly zero charging stations in Southern California, and that puts most of the 40-mile-range cars in a world of hurt as far as commuting is concerned. My own commute sits at about 42 miles round-trip, and I certainly wouldn't want to risk running out of juice in the middle of my commute. My previous commute was about 54 miles round-trip, well out of range, unless there was a charging station at work, which there isn't.
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RE: Green Power Claims
Neil
RE: Green Power Claims
Screwed from electric rates? I only get my electricty from a non-profit electric company.
RE: Green Power Claims
Oct. 23 (Bloomberg) -- California's push to lead U.S. sales of electric cars may result in higher power rates for consumers in the state, as a growing number of rechargeable vehicles forces utilities to pay for grid upgrades.
The autos' effect on electricity fees is being reviewed by California's Public Utilities Commission this month as the most populous U.S. state will require Toyota Motor Corp., General Motors Co., Honda Motor Co., Ford Motor Co. and Nissan Motor Co. to sell more plug-in vehicles from late 2011.
Power companies including Southern California Edison, the state's largest, have to install new transformers and meters to handle greater demand and prevent blackouts when autos are being charged at outlets. Utility rates will rise to cover the costs, said Travis Miller, a Morningstar Inc. analyst in Chicago.
"If you look at the kind of money that will be needed for a full smart grid and support for electric vehicles, then you are talking about a substantial amount," Miller said in a phone interview. The spending may total "multiple billions" of dollars over a decade or more, he said.
From model years 2012 through 2014, the largest carmakers by volume in California must sell about 60,000 plug-in hybrids and electric cars combined, according to the state Air Resources Board. President Barack Obama is aiming for 1 million plug-in cars on U.S. roads by 2015 to curb tailpipe emissions and cut dependence on foreign oil.
h
RE: Green Power Claims
Hmmmm.... maybe, one biomass plant.
Neil
RE: Green Power Claims
RE: Green Power Claims
Assuming energy equivalent of 0.3 kWh/mi, the energy consumed for an average of 40 mi commutes for 60,000 cars comes to about 710 MW*hr. Spread out over 12 hrs, that's only about 60 MW of load
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RE: Green Power Claims
RE: Green Power Claims
Nowadays, even if you could manage 20 mph, it would take you an hour to get to work.
....oh, it does take that long, now...
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RE: Green Power Claims
And what would be the expected maximum charging rate for each car? If it is a 120 V plug in, the maximum would about 12 A * 120V = 1440 VA each * 60000 = 86.4 MVA.
If every consumer, who could no longer buy an edison bulb, instead purchased a 20 W green bulb (example, I don't know of any bulbs this size) (60W-20W) = 40 W saved each, * number of customers (2 Million) = 2000000 *40 W = 80 MW saved.
The problem with any of this math, is that the load is probally growing anyway, and the electric grid expantion has to happen anyway.
So all this is pure spectulation. One large plant either entering or leaving your area could account for the same growth, or reduction in usage.