Thursday, December 18, 2008
Fuel-Cell Setbacks
Last year, the NY Times Magazine published a promising story on the future of fuel-cell powered homes. Now (10 Nov. 2008) they find that the company that was featured has yet to install a single new system. Too expensive.
Also Materials Technology (December 2008) points out that large-scale application of fuel cells depends on the availability of Pt catalysts, which material is in limited supply. Efforts to find a substitute are still in early development.
Tuesday, December 9, 2008
Cost of Conservation
To understand their thinking, consider a 25 W CFL bulb replacing a 100 W incandescent bulb. If the CFL burns for 8000 hrs, it saves 75*8000/1000 kW = 600 kWh. If the CFL bulb costs $6, it frees up (‘creates’) 600 kWh. So the cost of conservation is $6/600 or 1 cent/kWh.
OEC actually estimates the average cost to be somewhat higher if they average all energy-saving equipment, about 2.25 cents/kWh. I like to think that a saving is a saving and that people will save enough that the freed-up energy never needs to be generated.
Friday, November 28, 2008
Fuel-Cell 'Gas' Stations
In the hydrogen economy (which seems less likley than a few years ago) I envision the future 'gas' station to be equipped with a device to produce hydrogen from natural gas and a tank to store it. The motorist drives up to the station, plugs into the tank, and fills up his car. Thus the much-talked-about distribution system for hydrogen is easily provided.
The 'gas' station has advantages over other future technologies. Ethanol will still have to be delivered by tanker truck, which is expensive. Charging of electric cars en-route will be slow, unless the technology improves.
Tuesday, October 28, 2008
More on Electrical Usage
They also state that the average home uses 670 kWh/mo, which is 70% higher than our usage (see yesterday). This means almost 800,000 homes could be served with a 1000 MW coal plant.
Monday, October 27, 2008
Electricity per month
Saturday, October 25, 2008
Coal vs. Wind
Wind turbines need about 3 kW/home. So the efficiency of harnessing wind to produce electricity is in the same ball park as the efficiency for coal.
Tuesday, October 7, 2008
More Solar Economics Data
In his best month, he generated 806 kWh, which provides 115,200 kWh over 12 years. At $0.10.kWh, this comes out to around $11,000 worth of electricity produced - I don't see how he can break even.
Refs:
"Solar power users amass savings by folllowing the sun", Columbus Dispatch, 08 Oct. 2008
Stowell web page:
Tuesday, September 30, 2008
Energy Contest
"We are looking to reward the best energy savers in the Grandview Heights area. Since our scoring system allows small users to compete evenly with large users, everyone has an equal chance.
"How it works There are two contests: electricity usage and natural gas usage. Contestants can enter one or both contests.
"Electricity Find the item “Total Usage (Past 12 Months)”near the end of your most recent electricity bill (July or August 2008). Then find the same item on an earlier bill (January 2007 to July 2008). Record the numbers and mail to Al Rosenfield al.sustain@sbcglobal.net
"Example:
"August 2007 through July 2008 – 3071 kWh
"February 2007 through Jan 2008 — 3116 kWh
"Gas The procedure is the same, except that the number showing twelve-month usage is located at the bottom of the right-hand column on your bill.
"Example:
"September 2007 through August 2008 - 4868 Ccf
"June 2006 through May 2007 - 4985 Ccf
"All entries are due on August 31, 2008.
"Who is eligible To enter the contest you must pay an electric or gas bill for an address in the Grandview area, which means between the Olentangy and Scioto Rivers. The northern boundary is addresses on W. Fifth Ave. Everyone is free to enter - individuals, businesses, industries, and government.
"Judging The winners will be the contestants with the largest percentage decreases in usage. Here is an example of how it will work for gas:
"Contestant A Contestant B
"Aug 2007 through July 2008 – 4850 Ccf Sep 2007 through Aug 2008 – 1951 Ccf
"Feb 2007 through Jan 2008 — 5010 Ccf Nov 2006 through Oct. 2007 – 2057 Ccf
"Difference = - 160 Ccf (3.2 % of 5010) - 106 kWh (5.2 % of 2057)
"Contestant B wins because he made the effort to cut his usage by a bigger percentage, even though Contestant A saved more gas.
"There are two other requirements for winners to qualify. They must provide the judges with copies of their bills and an explanation of what they did to save energy. The judges can disqualify a winner if the saving is based on some unusual circumstances (got a programable thermostat is good, closed the house and went to Florida for the Winter disqualifies).
"?Prizes List needed.
"Any Questions Contact Al Rosenfield
Monday, August 25, 2008
Solar in AZ
The article also mentions that the average residential installation in AZ is 4 to 7 kW and costs about $8/W. The church cost was slightly less ($7.14/W for 14kW), suggesting that the cost benefit scales only slightly.
Wednesday, August 6, 2008
Tidal Power
Tuesday, August 5, 2008
Ethanol abd Food Prices
Monday, July 28, 2008
Wind Power (Champaign County)
130 turbines
$500 million cost
Each turbine will supply 800 homes
From this, I deduce:
Output = 2.3 MW/turbine = 2.9 kW/home
Cost = $3.85 million/turbine = $1.67/watt
This all seems reasonable. In light of other estimates I have seen.
Tuesday, July 22, 2008
Solar Cost
Ann plans to have a solar roof installed. It will be a mini-generator (all of the electricity will go to the grid). She will be receiving 42 cents per kWh over a 20 year term. The current rate she is paying is set by the local utility, Toronto Hydro, and not the province. It is approximately 11 cents per KWh.
The cost for a rated power of 2.34 kW is $22,485 (current exchange rate = 1:1) or $9.59/Watt. The is at the high end of the current price range of $8-10/W.
---------------------------------------------
An ad in Technology Review for July/Aug 2008 by SolFocus states that they will soon be producing photovoltaic for $0.24-0.28/W. and expect the priec to drop by half in two years. Still expensive!!
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More from Jerry:
You can check these websites for further information:
www.powerauthority.on.ca For further information on the Standard Offer
Contract
www.ontario-sea.org The Ontario Sustainable Energy Association. Their
recent report 'Renewables Without Limits' is the best critique I've read
of the current Standard Offer Contract, and offers a clear overview of
similar programs around the world.
www.wind-works.org Paul Gipe's website. He wrote the OSEA report, is
the acknowledged expert in this field, and the website will keep you
up-to-date on developments in the USofA. Paul can be a great help to you,
his email address is pgipe@igc.org.
Thursday, July 10, 2008
Wind Over-power
At the same time technologyreview.com reported that a waste to energy plant in Ottawa will produce 21MW per day, enough to power 19,000 homes - i.e. 1.1 kW per home. Lacking a better estimate, I'm assuming that other steady burners (coal and nuclear) also produce 1.1 kW per household.
The reason for this difference is that the wind doesn't always blow; storage batteries can be charged when the turbine produces more electricity than is needed. Even so, wind is not yet a reasonable source for a steady 24/7 electric supply.
Friday, July 4, 2008
Solar Opposition - Further to 20 June
Monday, June 23, 2008
Computer Electricity Use
I decided to check. Here are the data from The Texas Office of Risk Management:
Computer -------------- ----------------------- 250 watts
Monitor ----------------- -----------------------150 watts
Speakers --------------------------------------- 15 watts
Electric stapler ---------------------------------- 25 watts
Scanner ---------------------------------------- 150 watts
HP Laser Jet 4 Printer (Idle) ------------------- 250 watts
(Printing) ---------------1,175 watts
Total 840 watts when idle
1,765 watts when printing
It appears that the student’s estimate may not be far off. However, $1/day = $30/month is almost our entire electric bill.
We don’t have an electric stapler and our scanner is off when not in use. Furthermore, we have an ink-jet printer, which takes mush less energy than a laser. I figure that our system uses maybe 400-450 watts for 16 hours per day or around 200 kWh per month. which is maybe half of our electric bill. Still a lot!!
Friday, June 20, 2008
Opposition to Projects
The second proposed project was a wind farm in Garrett County, the westernmost county in Maryland. The turbines would have been built on state land in this mountainous region. Here the roles were switched. Out-of-towners thought it a great idea, but the locals strongly opposed it. They argued that Garrett County is a tourist region and the towers would spoil the scenery. Also, there was opposition to chopping down trees for the project. In the end the Governor canceled the project.
My reaction was the we will never fight climate change if everybody mounts his particular hobby horse.
Thursday, June 19, 2008
Gasoline Usage
Other statistics:
Americans used about 136 billion gallons of gas last year or about 550 gal/vehicle.
They also used about 7 billion gallons of ethanol.
Wednesday, June 11, 2008
There are adjustments to be made:
1. The US uses 43% of the world's oil (GAO).
2. These companies sell petrol in other countries.
3. Other companies sell petrol in the US.
Items 1 & 2 lower the profit per gallon and item 3 raises it. I don't have data for 2 & 3, but I find it hard to believe that the profits are less that $0.50/gal.
Tuesday, June 3, 2008
On Bridges and Cell Phones
Electronic technology seems to follow a very different path. New device follows on new device with ever expanding capability. But reliability suffers (an article in the NY Times this past Sunday pointed out that cell phones and VOIT are much less reliable than land lines).
Both the reliability and obsolescence of electronic devices promote a throw-away economy. It takes energy to make these devices and energy to dispose of them. I suspect that it's not much enrgy in the overall scheme of things, but it rankles a child of the Great Depression and WWII. We were taught to make do. I think that we are better for it.
Thursday, May 29, 2008
Useful "Facts"
1. Each five miles per gallon over 60 is equivalent to adding 20 cents to your price of gas.
2. Junk mail uses as much energy annually as 2.8 million cars.
3. Bottled water uses as much enrgy per yesr as 100,000 cars.
I don't know how accurate they are.
Wednesday, May 28, 2008
Hybrid Cars
Monday, May 12, 2008
Gasoline to Climate Change -1
Tuesday, April 29, 2008
Low-Hanging Electrical Fruit
Monday, April 28, 2008
Hybrid Economics
The first was about Chevy Tahoe SVUVs. The hybrid version cost about $10,000 more than the standard and got 4-5 mpg better mileage. At $3.50/gal this amounted to a gas saving of about $4,300 over 100,000 mi. For this vehicle, buying a hybrid has a net cost of about $5,700. Of course, if you buy an SUV, you’re not serious about saving the planet.
The second story was about New York City cabs, which will be required to get 30 mpg by 2012. Replacing the standard Ford Victoria with a Ford Escape hybrid saves the cabbie $175/week in gas but raises the rent that he has to pay for the cab by $135/week. So the annual savings are about $2,000. Since the Escape is ten percent lighter than the Victoria, the gas savings have two causes.
Friday, April 25, 2008
Fuel Cells
We could get hydrogen from natural gas, as the Japanese are doing for fuel-cell-powered home electricity. In fact, powering homes seems to be a more promising application than cars because introducing a new mass-production mass consumption power source should be simpler in a stable vs a moving application.Fuel cells are attractive for homes because they don’t need the sun to shine or the wind to blow.
Overall, I see hydrogen production as a major barrier to wide application of fuel cells. Some research should be devoted to this aspect of the problem.
Saturday, April 19, 2008
Electrical Ballast Definition
(from Wikipedia)
Monday, March 24, 2008
More on the R Factor
Energy-----R------Eff (%)----Eff/R----Cost
Source--------------------------------------$/W
Coal-----------5.9-----70----------12-------1.25
Nuclear------7.5-----90-----------12-------2.10
Hydro---------3.7-----35----------9.5------1.54
Biomass-----6.3-----50--------- 7.9------1.80
Geotherm.---6.4----80----------13-------2.20
Solar-----------1.3----20----------15-------5.00
Wind-----------2.0----25----------13-------1.18
Avg.----12.8
So R is essentially a function of efficiency. As an estimate:
-------------------------R = Eff/13
note: R converts MW to GWh or kW to 1000kWh
Friday, March 14, 2008
Wind Power
The defining equation is
RP = E
where R is the conversion factor, P is power in MW, and E is electricity in millions of kWh per year. I checked some data and found for wind that R averages 2.25 with most values between 1.9 and 2.6.
So if you want to estimate the annual output of a 1MW turbine, it's about 2.25 million kWh/yr.
I also averaged some cost data for wind power and found that:
C =1.62 - 0.24*lnP
where C is cost in $/Watt and P is Power in MW. So a 2MW turbine comes in at $1.45/watt, which is not bad
Friday, March 7, 2008
Chernobyl
A good example is Chernobyl:
56 World Nuclear Association
4,000 U. N. Chernobyl Program
16,000 International Agency for Research on Cancer
30,000 - 60,000 European Green Parties
140,000 Greenpeace
Note that the estimated number of deaths depends strongly on the organization's stance on nuclear power.
(I can't get this table to format correctly! but it makes the point)
Sunday, March 2, 2008
Electric-Powered Cars
(Written several months ago - may need updating)
Fuel costs the average driver about a dime per ten miles; a good gas/electric hybrid lowers that to about a nickel. Powering an all-electric car is even cheaper (1). The reverse is true for purchase price. All-electric cars are the most expensive and gasoline-powered ones the cheapest.
Hybrids are generally believed to be important energy savers, which is true if they are compared with gas guzzlers. However comparing the same make and model in both standard and hybrid versions reveals a different story. On average, hybrids cost about $6,500 more than standard versions and only get about ten mpg greater mileage (2). I made some rough calculations and found that the price of gas would have to roughly double to make a hybrid purchase worthwhile economically. With gasoline prices soaring (3) and electricity prices increasing only moderately (4), hybrids should become less of an economic burden. Hybrids also have the advantage over all other new car concepts, in that they can be fueled at any gas station. The gas tank can also be modified to take ethanol blends. There is some demand for them and about there are about 600,000 hybrids on the road now (5).
All-electric cars are not yet commercially available, except in golf-cart size. Conversion kits for full-size vehicles cost around $15-20,000, about half of that price if you install one yourself (6). Even at these prices, the break-even price on gasoline costs is somewhat less than for hybrids. All-electrics are also both the most energy-efficient auto technology and the quietest (7). Because all-electric cars can only go about 100 miles between charges, they can find use as ‘urban cars’, which take advantage of the fact that most cars travel only 40 miles on a typical day and can be recharged after the driver comes home at night.
Both classes of electric car will benefit from advances in battery technology to improve the range of all-electrics and to cut down the time needed to charge them. Plug-in hybrids (8), which are receiving increased attention, suffer from the same problems.
REFERENCES
(1) "Crunching the Numbers on Alternative Fuels", Popular Mechanics, May 2006 [2-42]
(2) Yahoo Autos
(3) Energy Information Administration Petroleum Navigator
(4) Energy Information Administration Average Retail Prices of
Electricity
(5) a. R.L.Polk News Index
b. R.L.Polk News Archive
(6) Electric Auto Association
(7) Michelin Challenge Bibendum, Paris 2006
(8) Plug-in Hybrids <www.sheryboschert.com/PowerPoints/florida.ppt.htm>
* Hydrogen-powered cars are sometimes considered electric vehicles. Because of their special problems, I consider them a separate class.
Thursday, February 28, 2008
Macro-Economics
consumers could save $13.5 billion
bulb manufacturers could gain $650 million
utilities would lose $12.85 billion (enough to build six nuclear reactors).
Saturday, February 23, 2008
CFL Bulbs Save Money
95% of the cost of an incandescent is the cost of electricity, compared to about 3/4 for CFL.
The total cost of a CFL is about 1/3 of the six incandescents needed to get the same amount of lighting.
There is no break-even point for buying bulbs - the total incandescent cost exceeds the CFL cost after 700 hours, which is below the incandescent lifetime.
-----------------------------------
Details of calculation:
CFL = 25W costs $5.00 & lasts 6000 hours
Incandescent = 100W costs $0.50 & lasts 1000 hours (need 6 bulbs to equal 1 CFL)
Cost of electricity = $0.091/kWh (in Columbus, Feb. 2008)
Thursday, February 14, 2008
Global Warming is a Materials Problem
Glass/polyester wind turbine blades have higher stiffness
Glass texture improves efficiency of solar cells
Fuel cell powered by sunlight on titania-coated electrode
The magazine also reports about five other weight-saving developments in more mundane applications - save weight = save fuel!
Wednesday, February 6, 2008
The Big Energy Wasters
Since electrical transmission is a small part of the loss, it's clear that the best thing we can do is to make power plants more efficient. And, if Wikipedia is to be believed, the technology is available to increase plant efficiency. If we only look at greenhouse gasses, we need more nuclear - no improvement in efficiency, but a big drop in emissions.
For transport, Congress passed a law increasing mileage on cars and Light-trucks/Vans/SUVs. According to the Energy Information Administration, car mileage has been trending upwardsfor about 30 years, while vans, etc. have plateaued since 1990. But big trucks have made no gains in mileage for 40 years. I find this hard to believe, so will check further.
Tuesday, January 29, 2008
Traffic Lights
The large cost savings from LED traffic signals is well documented. What I didn't realize is the change in where the money goes. The cost of an incandescent light is trivial compared to the cost of the electricity it uses, while the cost of the LED signal is significantly higher than the electricity. Conversion to LED takes money from the electric company and gives it to the lighting manufacturer.
Saturday, January 26, 2008
Mnemonic
Everyone should do their BIT to save energy:
Buy low-energy items
Include energy conservation in building and remodeling plans.
Turn things off when not in use (or lower the power it that’s not possible)
You will save money and do a favor for the environment.
Tuesday, January 22, 2008
Elevators
You stand by the elevator and read the poster “Walk up one and walk down two for your health”. You will also save lots of electricity - elevators are energy hogs. Each one uses a much power as hundreds of light bulbs. So walk up one and walk down two and save energy.