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SETI Sucks Power

The entire point of the SETI@home project is to exploit the massive computing power of millions of unused personal computers, and the project has broken new ground in processing radio signals from outer space. But as much as the SETI@home project is attempting to advance human knowledge in a low-impact, collaborative, cost-effective manner, there is a side-effect that some people may not consider – the electrical power consumption necessary to run the computers participating in the SETI@home project.


In many parts of the world, people have made the individual choices that they in essence wish to subsidize SETI@home by paying their power bill, but given the significant electrical problems faced by the State of California right now, decisions to use power for non-essential activities like SETI@home have become more complex. There are many reasons – both good and bad – people don’t turn off devices which consume electricity, and I’d like to encourage everyone to step back for a moment and remember that unrestrained use of electricity can have negative consequences. Perhaps California’s woes can help us all take the extra few moments to revaluate our power usage habits and reduce them when appropriate.

Recent Power Mac G3s and G4s consume between 200 and 250 watts (that’s without a monitor), while a typical 27-inch television consumes less than 150 watts. So, in general terms, running a computer 24 hours a day can consume between 33 and 66 percent more power than leaving a television on all day long – something few people would do in a power crisis. (Current iMacs consume 150 watts, but earlier models used as little as 80 watts.) Of course, judicious use of Apple’s Energy Saver control panel or St. Clair Software’s Sleeper control panel can significantly reduce power consumption without the delay of waiting for the Mac to boot from scratch.


Thanks to Jim Carr <[email protected]> for raising this issue, and kudos to the SETI@home project for explicitly asking California users to shut down their computers to conserve power. Jim wrote:

"I am currently 24th on TidBITS team for the SETI@home project with over 2 years of CPU time and 1319 work units completed. Alas, my unit production will be drastically curtailed for a while.

< cmd=team_lookup&name=TidBITS>

I live in a part of Southern California that receives power from Edison, which is having financial problems and is unable to pay its bills for more power. Other California utilities are in same situation, and there is just not enough reasonably priced power available to the state grid to meet demand. Rolling blackouts have already begun in California.

I achieved my SETI@home totals by leaving a computer (along with a second one for the last few months) running 24 hours a day, every day, and 90 percent of that time is spent calculating SETI@home work units. I feel that it is no longer socially responsible to do that anymore when the public is being asked to conserve as much power as it can.

I want to urge all users out there who are in a region affected by power shortages to shut down equipment when you aren’t actively using it. I remain a supporter of the SETI@home program and have also supported it via membership in the Planetary Society. I look forward to the day when the power mess is resolved in this state and I can run those computers without feeling guilty."

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