"Powers 140,000 Households' ... Just "WHAT" is a (US) "Household" Power uni 2

[racookpe1978]

SO, the propaganda/publicity machines promote a California desert solar complex costing 1.6 billion dollars as providing "140,000 households" with power .... Obviously implying that dirty/evil/nasty/carbon-dioxide polluting" regular power plants will not have to to provide any power to these 140,000 households since the solar plant is on-line burning up birds every 2 minutes as it provides power ....

OK. So please put up with the fact that I am prejudiced against the taxpayers providing 1.6 billion dollars in loan guarantees to a group of tax-paid companies to incinerate innocent birds flying over the otherwise pristine deserts of southern California.

Just what is considered a "household" when the publicists write their press release? A full year's of electric power? An averages "per captia" power use times an assumed "people per house" (or apartment) use for a year?

An "ideal" power at "maximum output at noon on a perfect low humidity day on June 22" divided by the "average power per house per day for a year"?

The US Energy Information Agency (as if we needed a government agency to identify energy abbreviaitons) does NOT even list "households" as a item in their list. Nor does anybody else for that matter. The closest is a "study" done for California by a California PhD payee who used

"Total Electricity usage (all applications) per year for comparison:

USA 12,000 kWh per capita

California 8,000 kWh per capita
Average of SC Edison and San Diego Gas and Electric

Household electricity use: 6,000 kWh per household per year for 3 residents average per household. So the household use per capita is 2,000 kWh or about ¼ of per capita electricity from all applications.



Household Natural Gas use: 400 therms per household x 30 give 12,000 kWh equivalent electricity. Since much of the electricity is generated by natural gas, it is not totally unreasonable to compare these two in kilowatt hours. We note that heating water and households by natural gas uses twice the power of household electricity.



Total average household power usage:

6,000 kWh electricity plus 12,000 kWh gas equivalent = 18,000 kWh per year."

in one of his analysis for CA to increase subsidies for green energy in CA in 2010.

But even there, in a prejudged study, he could not get a "standard number" for a household.

I see hundreds of times a year, the "number of households" that some given publicity stunt will provide to justify more tax payer subsidies.

But what is this number?
How is any given scheme for green power set up: Maximum potential output at high solar noon on a clear day in mid-summer?
An :average" day at noon in mid-winter?
A cloudy day in October?
A "yearly average day" across the whole year for 12 hours - when a gas turbine is required to pick up the rest of the load burning up its turbine and rotor trying to adjust a rapidly changing load each hour?
A yearly "average" delivery when a wind turbine only has a 21% efficiency rating?
The maximum number of assumed households yearly electric use divided by 365/24 ... then the maximum wind turbine output divided by that "yearly average value" ?
The maximum household loads at 5:30 in the south in July when AC loads are at their maximum?
The hourly load in the north at 22 January when heating bills are highest?

I KNOW it is propaganda. I accept that - our administration and the ABCNNBCBS news media are going to publicize only the "facts" that they want to promote. But ... What is a "US household" and who determines it when they write the propaganda?

 

[Compositepro]

The number that I recall generally being used is 5 kW. It is akin to relating a 100 ft height to a ten story building, very crudely descriptive.

 

[itsmoked]

You want the number?

2,800W

.
.
.
.
.
.
392 megawatts / 140,000 = 2,800W

Keith Cress
kcress -

http://www.flaminsystems.com

 

[LionelHutz]

There will have been some calculation giving the expected kWh output of the solar plant over a year using the yearly average sun energy available. That was divided by some average kWh value for a typical home, similar to your 8,000 kWh number.

I highly doubt they combined electricity and gas usage. They are making electricity so they will talk about supplying alternative electricity to these houses, not total energy.

Keith - nice pat answer but it's meaningless.

 

[cranky108]

My guess is they don't power any households at night.

It's just a number used to brag about how powerful the plant is. It's ment to impress, and win public support for a project that makes the vultures happy.

The annual consumption of energy of a household is a guess, as some people without air-conditioning consume less energy, and people like Al Gore consume much more.

This is a prime example of man impeding on nature, and displacing the native wildlife, for the goal of some save the planet clean energy scheme.
The problem is it's unreliable, and unsustainable, jobs program for the green movement.

 

[bacon4life]

At my utility, average household consumption is 1.5 kW (11,606 kWh/year). We serve ~435,000 people and have 150,310 residential class meters per our quick facts brochure.

More than half of our energy is consumed by commercial and industrial customers, so the "average electricity used per capita" is more than twice the "average electricity used by a person at home."

 

[jraef]

My guess is they don't power any households at night.

Sure they do, it's just that it is "dark" energy!
The problem really is that our appliances lack the necessary adaptation to utilize it.

"Will work for (the memory of) salami"

 

[Compositepro]

When calculating the generation capacity the power company has to have in place, you have to use the average between all customers at the time of peak usage, not the average for the whole year. In many places the peak tends to be hot summer days. Solar might make sense for this. It is not going to help with the peak that occurs at half time during the Super-bowl.

 

[cswilson]

Since almost no one has a good intuitive concept of what a unit like a gigawatt means, I don't have a fundamental problem in converting it to something like "households powered".

My problem with their calculations comes from the fact that they use the peak capacity of an unpredictably intermittent plant (at least when using solar) and divide it by household average usage. Apples and oranges...

 

[cranky108]

The news media is full of simple people. 1 + 1 = 3 They understand that.

The problem is solar peak is from like 11AM to 3PM, when the electrical usage peak is around 4PM to 7PM (depending on location, and time of year). And so in effect it makes the peak supplied by convential generation much sharper and more difficult to ramp up to.

 

[Electic]

Not only with the solar plant NOT power any households at night, the entire conventional distribution and generation system will still be needed to supply night time demand, nothing gets displaced by alternative power. The cost of electricity has much to do with the maintenance and operation of conventional distribution and generation systems, and only a very small percentage originates from the price of fuel.

So the solar plant is simply added cost burden for regular power users, to pad the pockets of an (oftentimes foreign) investor, mandated to make his money by green initiatives.

 

[bacon4life]

It is apples to oranges to convert almost any kind of power plant output into homes:
1. A nuclear plant runs 24/7 at a constant load, and generally does ramp up or down to accommodate changes in load. During overnight hours, having too much nuke power can force other plants offline. After a blackout, Nukes can take many days to return to full power.
2. A peaking gas turbine might run less than a few hundred hours a year, but is quite valuable when it is needed.
3. A hydro plant may have limited flexibility to load follow either do to spring flooding or do to river (fish) constraints.

 

[prc]

It is the job of engineers to sell the investment idea to public by attracting their attention and imagination. Electrical engineers were always doing this during development stages of electric power. The most interesting case to my knowledge- When GE made a large generator (may be 20 or 30 MW) first time,marketing manager approached Dr Steinmetz for a catchy story to go with the announcement.The wizard with in a split second,after scribling on a piece of paper came out, the output power of this generator is almost same as the maual power output of all slaves employed during Lincon's time before the civil war.

 

[catserveng]

While I don't agree with many of the assumptions in this paper, at least they try to cite reputable sources and use ARB and CAL ISO calculations, and actually define a number for kwh per household.

http://www.firstsolar.com/~/media/d...chnicalreportcarbondisplacement_02761_na.ashx

When a large number of landfill and digester gas powered generation units were going in to California several years ago this was a term used widely then as well, and with lots of variations. PG&E had (for a while at least) a value on their old website of around 350kwh per household (from an old piece of literature I have dated 1996). When the Miramar Landfill Gas Energy project went in in the late 1990's, SDG&E said it powered "14,000 homes". The plant had 4 X 1.6 MW tandem drive generators with a typical output of 100% rated and an uptime of about 94%, which roughly calculates (using a 30 day month)to about 310 kwh/month per home. So kinda in the ballpark I guess.

Problem is where I live near the coast my average usage is about 250 kwh/month, a friend of ours 25 miles inland with the same size house in around 650 kwh/month, so what is a "real" average kwh/month in any given area?

my 2.5 cents worth, Mike L.

 

[marks1080]

Throw the concept of Spinning Reserve into the equation and you really start to find out that alternative energy really doesn't offset CO2 emmissions. I believe Germany at one time had so much wind power installed they had to burn more coal than they did before the wind mills went up just to support the Spinning Reserve, which is essential for system stability.

 

[stevenal]

I commonly see where a facility will power "(X) homes per year. What if you need to power (X) homes for two years? Do you need a start building that second replacement facility?

 

[bacon4life]

marks1080,

Last year NREL published a report for the western USA comparing the increased emissions from loss of efficiency during ramping and spinning reserves to the decrease in CO2 emissions from normal power production. When looking at ~25% renewables, CO2 was decreased by ~30%, even including increased spinning reserve, part load loss of efficiency and ramping of fossil fuels.

http://www.nrel.gov/docs/fy13osti/55588.pdf

 

[cswilson]

stevenal:

I almost never see an article on this type of topic in the mainstream press that does not confuse power and energy at some point...

 

[racookpe1978]

Last year NREL published a report for the western USA comparing the increased emissions from loss of efficiency during ramping and spinning reserves to the decrease in CO2 emissions from normal power production. When looking at ~25% renewables, CO2 was decreased by ~30%, even including increased spinning reserve, part load loss of efficiency and ramping of fossil fuels.

And I have stood inside the exhausts of gas turbines forced to rapidly startup and shutdown daily (hourly!) to withstand the vagrancies and transients and unpredictable power from those windmills ... and looked out at the blue skies and nearby mountains through the cracks in those hastalloy exhaust plates ... caused by the multiple and excessive heatups and cooldowns from the waste that is demanded by the politicians and their wind power cronies.

So, the NREL - a government-agencies funded for promoting such windmills, admits that all of their promotions - at best - reduced emissions by raising the costs of electricity by 30% while raising emissions on the conventional power plants by 25% ?

 

[prc]

Let me correct my earlier posting as it was from memory. I found my scrapbook and facts are as below : (Source GE Review,July,1957)Occasion (early 1920's) was GE sold a record 60 MW turbine-generator to Commonwealth Edison company,Chicago and the top boss wanted publicity manager C.D.Wagoner to have the news in the front page in newspapers on the next day. He approached the engineering wizard of GE at Schenectady,C.P.Steinmetz(1865-1923).What Steinmetz jotted down while explaining to Wagoner QUOTE
"One KW of electricity equals 1.34 HP. So 60,000 kW would be equivalent to about 80,000 hp. And one horsepower is equivalent to the muscle work of 22.5 men.So 80,000 hp would equal the muscle power of 1,800,000 men.But a turbine requires no rest;it works 24 hours a day,three 8 hour shifts.So we mutiply the 1,800,000 by three.So energy equivalent of 60 MW Generator is muscle work of 5,400,000 men.That's greater than the combined muscle power of all the slaves in the Unites States before the Civil War." His quick,clear explanation amazed me (Wagoner).In jotting down these figures he had used no reference books.I thought he might be wrong on the slave population angle;and after leaving his office,I checked the figure,only to find that the slave population in 1860 was 4,700,000. UNQUOTE