223 comments on DrumBeat: May 30, 2007
Comments can no longer be added to this story.
Show without comments | PDF version
223 comments on DrumBeat: May 30, 2007
Comments can no longer be added to this story.
Show without comments | PDF version
Search The Oil Drum with Google
Support The Oil Drum
Recently on TOD:World
TOD:Campfire
TOD:Europe
- Peak Gold, Easier to Model than Peak Oil? - Part I
- Carbon Capture and Storage
- Oilwatch Monthly November 2009
TOD:Canada
- In this house, we obey the laws of thermodynamics!
- The Round-Up: October 24, 2008
- Compressed Air Energy Storage - How viable is it?
TOD:Australia/NZ
- International Energy Agency calls 'Peak' on OECD Oil Demand
- Australian Senate: Peak Oil motion defeated 31:6
- The Bullroarer - Friday 20th November 2009
TOD:Net Energy
Blogroll
Energy Sites
- The Coming Global Oil Crisis
- Die Off
- Dry Dipstick
- Energy Bulletin
- From the Wilderness
- Life After the Oil Crash
- Peak Oil Crisis
- Peak Oil News and Message Boards
- Powerswitch
- Rigzone
- Matthew Simmons
- Wolf at the Door
Environment & Sustainability Sites
- The Daily Green
- EcoGeek
- Eco Street
- Green Car Congress
- Green Options
- green.alltop.com
- Gristmill
- RealClimate
- Sustainablog
- Treehugger
- WorldChanging
Blogs
- Casaubon's Book
- Cleantech Blog
- Clusterf
k Nation (Jim Kunstler) - The Cost of Energy
- David Strahan
- Early Warning
- The Energy Blog
- European Tribune
- GraphOilology
- Health After Oil
- jeffvail.net
- Mobjectivist
- Peak Energy (Australia)
- Peak Energy (USA)
- R-Squared
- Resource Insights
Finance & Economics Blogs
- The Big Picture
- Calculated Risk
- The Crash Course
- Ecological Economics
- Econbrowser
- Environmental Economics
- Infectious Greed
- The Mess That Greenspan Made
- Mish's Global Economic Trend Analysis
Organizations
Peak Oil Primers
Beware email scams!
Beware email scams claiming to be from this site. We do not have any job openings. If anyone contacts you about a job at The Oil Drum, do not reply to them, and definitely do not give them any personal information or send them money. Read more here.
“It takes as much energy to wish as it does to plan.”
—Eleanor Roosevelt
User login
Contact
- Content: editors at theoildrum dot com
- Tech support: support at theoildrum dot com
Personnel
- Editors: Nate Hagens, Gail the Actuary, Prof. Goose
- DrumBeat Editor: Leanan
- Contributors: ace, Engineer-Poet, Heading Out, jeffvail, JoulesBurn, Sam Foucher, Robert Rapier
- TOD:Campfire: Glenn, Jason Bradford
- TOD:Europe: Chris Vernon, Euan Mearns, Francois Cellier, Jerome a Paris, Luís de Sousa, Rembrandt, Rune Likvern, Ugo Bardi
- TOD:Canada: benk, Libelle
- TOD:ANZ: Big Gav, Phil Hart, aeldric
- Emeritus: Stuart Staniford
- Technician: Super G
License
This work is licensed under a Creative Commons Attribution-Share Alike 3.0 United States License.










GAIA Host Collective
Wow, I got quoted.
A watt-hour isn't very much. So it's not so surprising that a big TV uses a lot. By a strange circumstance, electric cars and video projectors are two of my biggest interests.
Most video projection technologies are "light valves". That means that a bulb provides a constant light source, and some arrays of shutters act to block part of that light to form an image. Even film projectors are light valves. So the standard output of the bulb is the baseline for the projector's power consumption.
Fortunately great strides have been made. My old JVC G10 front projector used a 400 watt xenon arc bulb for outstanding color accuracy, but it only lasts 1000 hours, and I simply couldn't afford to replace it. My new projector, an Optoma HD70 DLP, cost me $850, is brighter, has a much better contrast ratio, and uses a 200 watt bulb. Furthermore, I run it in the low output setting to increase bulb life to 3000 hours and reduce heat rejection.
The problem is, I keep forgetting that when I stop the player, the screen goes dark but the bulb is still cranking away in there. I try to limit use to 2 hours a night, but I keep pausing the movie for things.
The next goals for power reduction are the use of LEDs as bulbs, and the replacement of plasmas and flat LCD panels with OLED panels. So far, the former are limited to conference-table screens.
As for cars, I know of some watt-hour figures for some other vehicles. The Prius is commonly said to consume 250 watt-hours/mile. However, a dozen years ago AC Propulsion converted a Civic to run on lead-acid batteries:
"In June of 1996, at 77,000 km, the AC Propulsion electric vehicle traveled 233 km (145 mi) on one charge over Southern California Edison’s Pomona Loop, a 31.2 km (19.4 mi) circuit of city streets in and around Pomona, California. The Optima spiral-wound lead-acid EV batteries had been installed at 65,000 km, and the new range mark represents a 23% improvement over the best range achieved with the previous generation Optimas. The AC Propulsion EV completed the range test with an average energy consumption of 78 Wh/km (126 Wh/mi)."
I have to wonder what they knew that GM did not. Top speed was about 80 mph, 0-60 in 6.2 seconds, and a weight of about 3500 lbs.
Solectria also did some great work in those days, building a handful of Sunrise composite sedans in lead-acid, NiMH and lithium ion versions:
"Solectria Corporation announced today that unofficial
results indicate the Solectria Sunrise electric sedan powered by Ovonic
Nickel-Metal Hydride batteries set a new electric vehicle range record by
completing 375 miles on a single charge in the third day of racing in the
1996 NESEA American Tour de Sol, the national solar and electric vehicle (EV)
championship."
Here's pictures:
www.austinev.org/evalbum/655
The secret is the weight.
I keep seeing the citation that the Prius uses about 250 Watt-hours per mile. I think it is not right. I suspect the true number is closer to 100 to 150 Watt-hours per mile based on my experience.
Whoa, I've gotta call bu!!sh!t on this one. The energy equivalent of a gallon of gas is about 36kW-hours...are you saying the Prius gets 360 to 240 miles per gallon? Even 250 Watt-hours per mile would be 144mpg evquivalent - BS on that too. Now 600 Watt-hours per mile I can believe.
Didn't someone in here say that electric power to the wheels is about 90% efficient and gasoline is 10% to 15% efficient -- so (taking the best ratio of 9x) your Prius numbers go to 40 to 26 mpg. No?