The City of Seattle has made developing a goal for citywide carbon neutrality by 2030 a priority. In September 2010 the City held a forum in which workgroups gave presentations on carbon neutrality strategies in various disciplines. At the time I noted a lot of incrementalism, and very little vision of a city at zero emissions.
For each significant category (>3% of the total emissions) in the City of Seattle 2008 carbon emission inventory, below I list whether reaching zero emissions is primarily a matter of government policy, culture or technology.
Cars (20% of total): Policy and culture. Walking, biking, electric transit and electric vehicles can entirely eliminate fossil-fueled personal vehicles.
Trucks (18%): Technology. Battery power is unlikely to be effective for freight trucks due to energy density, weight and cost. Rails aren’t everywhere that goods need to go.
Air (18%): Technology. Non-fossil fuel solutions to air transport are yet to be determined. Reducing air travel is an interim step.
Natural Gas (16%): Policy. The City can shut down the natural gas distribution system. Users, given sufficient notice, can migrate to electric appliances and/or retrofit for energy efficiency.
Cement production (11%): Policy and technology. Policy can force install of the best available emissions reduction processes, or fund low-carbon cement research. But technology is needed to go to zero.
(Other sources combined are 17% of emissions.)
The City of Seattle has the capability to be carbon neutral in several categories by 2030 through policy only. The city is blessed with carbon-neutral hydropower for electric supply. For neutrality, the city’s electrical demand needs to be kept within the capacity of the hydropower system, supplemented by other renewables such as wind. The key to achieving this is to be aggressive about electrical efficiency as activities are transitioned from other fuels, such as personal vehicles or natural gas furnaces, to the electric supply.
Technological progress is needed in three major categories to reach zero: trucks (goods transport), air travel and cement production. I will write about each of these items in upcoming posts.