Climate Change Recalculated

Speaker: Saul Griffith, MacArthur Fellow

Sponsored by: The Long Now Foundation

Tonight, Presidio MBA classmate David B said that he was going to hear a speaker at Fort Mason that had invented a lot of stuff, but that he wasn't a very interesting speaker. So some of us tagged along not expecting much. However, we were in for a pleasant surprise! Saul Griffith turned out to be a very interesting and entertaining speaker and talked about how much energy we use, what we can do to reduce this and what would be necessary to move to a sustainable energy future. Right up my alley! He threw out a lot of information and I haven't digested it all, but here are the notes I took:

Power for Saul's Life

• His 2007 life: 17k to 18k watts. This is from his travel, food and material items he buys. (I usually think in terms of energy - kWh - so I still have to wrap my brain around his analysis based on power. I guess this means that if you take the entire energy he uses for a year, and divide it by the number of hours per year, that is the power he uses each hour.)
• Not counted is the embodied power in roads, which works out to about 330 watts per person
• Qatar uses the most power: 27k watts per person
• US users 11k watts per person, so Saul uses quite a bit more
• Global average  is 2.2k watts

What would it take to switch to renewable energy?

• There are still 1600 giga tons of carbon in fossil fuels
• Humanity uses 16TW of power
• To keep CO2 to 450 ppm, we can only burn 3TW of fossil fuels
• Currently 1.5 TW comes from renewable sources
• So we need to produce 11.5 TW from new renewable sources
• To produce 2 TW of power for next 25 years would need to install:
  
  • PV: 100 m2 per second
  • Solar thermal: 50m2
  • Wind: one every 5 or 6 seconds
  • Nuclear: 1 power plant every 3 weeks
• Can we do it:
  • GM + Ford could make 1 wind turbine every 5 second
• In 40 years world installed 10TW of power, so we should be able to do same with renewable
• It will take a lot of space though:
  • PV is 10-20 watts per m2 land
  • Wind 1-2 w/m2
  • Hydro 2.9 w/m2
  • Bio-fuels 2-3 w/m2
  • 10 TW of power would need land size that would be the 7th largest country in the world
• 41×41 m2 needed to power Saul’s life

Saul's life with less power

• Shoot for 2200 watts
  • Fly once a year to East Coast
  • Every 5 years go to Australia
  • Drive 100 mpg car 20 miles per day
  • Meat once a week
  • Own 1/10 less stuff and make it less 10 years
• 1/4 of the energy we use is in stuff
• This year he is using 12k watts which increased his quality of life
• Wattzon.com shows energy used in units of oil

How to reduce CO2 emissions?

• Important: Turn off old carbon emitting power plants, stop deforestation
• Reduce speed limit to 55 or less
• Use electric motor scooters

Questions

• High altitude wind is higher density, maybe as much as solar
• Only ‘get out of jail card’ is fusion and we have been reducing funding for fusion. But fusion will still take time.
• Carbon sequestration is still unknown
• Carbon offsets don’t work. see Cheatneutral.com
• Biofuels have too much investment for their potential benefit
• Negative feedbacks for climate change not known
• Geo-engineering to reduce temperature not good solutions. Dan Shrank at Harvard.
• $2-$4 watt solar, $2 wind. Need $25 trillion to solve problem
• High altitude wind, enhanced geothermal, tidal could be running in 5 years. Efficient biofuels will be longer.
• If we reduce speed limit, we reduce the top 5 causes of death: heart disease, car accidents, obesity, diabetes