In the near term, electric cars can begin to replace many gas powered cars.  An electric car uses about 300 Whrs per mile worth of electricity.  Introducing 50,000 electric cars in Seattle over the next 5 years, each driven 12,000 miles a year would add 180,000 MWhrs to local consumption, or 20.5 MW continuous, only a 2% increase in total electricity consumption. Eventually, perhaps half of the cars in the city can be replaced with electric, which would only require a modest increase in the electricity supply.  It is likely that battery storage technology will soon  advance to the point where consideration of stored chemical energy for surface transportation fuel can largely be eliminated.   Supplemental compressed hydrogen may be the the simple answer for surface transit, but such a solution is bulky.  For the broader aviation market,  even cryogenic hydrogen does not seem adequate in terms of energy density.   Thus, for both surface and air transport, the development  chemical hydride storage seems inevitable.  Seattle City Light should forge a path to the post-carbon new industrial age with a pilot carbon-free fuel plant based on sodium borohydride at the WPS-1 site in Richland.

Sodium borohydride is a high-tech fuel, currently expensive, used in fighter jets and rockets.  A closed NaBH4+H2O=NaBO2+ H2 cycle can be driven by molten salt electrolysis.  NaBH4 has about the energy content of gasoline, in the same size and weight of liquid fuel.  Estimates are that when developed on an industrial scale, the borax can be converted back to borohydride with a 50% electrical efficiency. Coupled directly to a high temperature nuclear reactor, efficiency should be much higher, on the order of 75% or more.  A  GT-MHR module puts out about 285 MWe, or 6.84 GWhrs per day.   A gallon of gasoline is equilvanent to about 10 kWhrs of electricity.  Assuming 75% efficiency, the equivalent of 500,000 thousand gallons of gasoline equivalent fuel a day would produced, about 1/3 of current fuel consumption in the city, enough for 150,000 vehicles. At $1 billion for the reactor and $1 billion for the balance of the fuel plant, financing this combination would cost about $400,000 a day. Labor and O&M and transport would be about $150,000 a day.  Providing a subsidy of $6000 per vehicle to convert 150,000 vehicles in the city to dual fuel (gas/borohydride) [by adding a fuel processor and turbocharger to the engine] adds $175,000 a day.  The cost of production for this alternative to 1/3 of fossil fuel needs is therefore about $725,000 a day.  At $2.75 a gallon, Seattlites currently spend about $4 million a day for gasoline. Replacing 1/3 of this consumption is worth $1.3 million a day.  With this approach, converting a third of the vehicles  in the city would produce about $575,000 per day or $225 million a year in revenue to the city, while cutting greenhouse emmissions by 1/3. Once proven, additional modules could be added to the existing plant at Richland for ever greater wealth and cleaner air for the city.  Naturally, the industrial spin-off would make us richer than the Emerald City of Hollywood fame.