Freitag Jan 16, 2009
Montag Jan 12, 2009
By rolfk on Jan 12, 2009
After the Sunday Times had published last week that Alex Wissner-Gross estimates the same number Google now officially has answered.
I was wrong. Very wrong. Wrong by a factor of 35. Wrong even when you take into account that Moore's Law and Google engineers had 20 months to increase efficiency since my first guestimate.
So now we have it: One Google Search produces as much CO2 as 10 seconds of breathing!
Update: Could be that the Sunday Times directly took my number (after generating 0.2 grams of CO2 and finding this blog with a Google search) and connected it to other work done by Alex Wissner-Gross. Funny how an innocent number can make big news 20 months later!
At least I got my 2 seconds of fame on Techcrunch: "This obscure blog post" ... "Rolf Kersten’s Weblog (who?)" Cheers!
Mittwoch Aug 15, 2007
By rolfk on Aug 15, 2007
Durch die Sun EcoTour auf uns aufmerksam geworden, hat Elita Wiegand mich eingeladen, eine Reihe von Gastblogs zum Thema "Green IT" auf ihrer Innovativ-In Plattform zu posten. Hier die Links zu meinen fünf Postings:
- Teil 1: Das Mitmachweb und der Klimawandel
- Teil 2: 1.000.000.000$ Stromrechnung - eine gute Nachricht für das Klima
- Teil 3: Leichter leben mit der Smart Card
- Teil 4: Ran an den Strom
- Teil 5: Wie vermarktet man Green IT?
Freitag Jul 13, 2007
By rolfk on Jul 13, 2007
Can you operate a datacenter without producing CO2? STRATO - the biggest webhoster in Germany - claim they can. They plan to buy their 30 Gigawatthours of electricity they need each year from a hybrid plant.
Sun is showing neat Blackbox pictures like the one on the right.
A Blackbox is a datacenter in a box - capable of running and cooling hundreds of servers drawing 200 Kilowatts of power. Let's see - a wind turbine producing 200 Kilowatts of electricit is no rocket science these days. Repower already builds monster turbines with a propeller diameter of 126m and 5000 Kilowatts rated power. But wait a minute: We cannot calculate with rated power, because the wind is not blowing with full speed 8760 hours/year. So what is a typical yield factor of a wind turbine?
End of 2006, wind turbines with 20,6 Gigawatts of rated power were installed in Germany, producing 30.600 GWh of electricity in 2006. That's a yield factor of 17%. Not bad.
So when adding a really big battery to the picture above, a wind turbine with 200 KW / 17% / (battery effciency 80%) = 1500 Kilowatts of rated power would be sufficient to feed a Blackbox. That's the smallest turbine Repower offers these days.
This is exactly why the Blackbox is not only clever engineering to cram as many servers as possible in a small footprint, but also an ecologically responsible concept. Do not bring (CO2 emission tainted) electricity to your datacenter, build your datacenter where CO2-free power is available!
Mittwoch Jul 11, 2007
By rolfk on Jul 11, 2007
The last five days, Martin covered the first 300 kilometers of his EcoTour through Germany. The vehicle carried the pedaleur himself, luggage for a week and provided protection from heavy rain showers. Looking at other vehicles meeting these specs, how does the EcoRider compare?
Enter the competitors:
| BMW C1 motorbike|| Smart FourTwo CDI|| Sun EcoRider|
| Power Source||Gasoline||Diesel|| Muscle/Electric power|
| Consumption|| 2.9 liters/100km|| 3.2 liters/100km||2.2KWh/100km|
| CO2 emission||77g/km|| 88g/km||22g/km|
| CO2 per person||77g/km||44g/km||22g/km|
The CO2 emission of the EcoRider was calculated as if all the electric power would have been created by using a Diesel powered generator with an efficiency of 30%.
So even with homegrown inefficient power generation, using the EcoRider for dry trips with luggage up to 70km is better for the CO2 balance than everything else. And better for your health.