Penny a kWh

Penny a kWh electricity

Why try to get space-based solar power (SBSP) down to a penny a kWh?

This has to do with price elasticity of demand.

Some points on the curve:

• At a dollar a kWh, the demand is near zero, a small number of military camps that would draw a few MW.
• At ten cents a kWh, SBSP could pick up Hawaii's electrical demand of a GW or two except that SBSP power doesn't easily come in small blocks.
  • For the rest of this analysis see http://www.coal2nuclear.com/energy_overviews.htm (and ignoring the small difference between a Quad and an EJ)
• At four cents, SBSP gets most of the electrical power of the US, about 400 GW plus the rest of the world for another 1600 GW. (Half average price for power. Distributing electricity costs too.) Building 2000 GW (four hundred 5 GW power sats) takes 4-5 years. Gross income from power sales (the power satellites could also be sold) at 4 cents per kWh would be would be 2,000 GW x 4 x $80 M/yr/GW or $640 B a year, though some of this would have to be sold for less as off peak power.

In the early years, extra rectennas will allow a premium for switching blocks of peaking power around. Later, North American off-peak power in excess of base load can be switched to Canada to make hydrogen to upgrade tar sands oil. This would raise the effective amount of oil since current extraction/upgrades burn one barrel for each 3 produced.

As the cost of power declines to a penny a kWh, space-based power picks up the entire oil and gas markets. The only source that competes is installed hydro.

Cost of power sats

Penny a kWh power sells for $80/kW/year. Using a simple payoff in ten years, that requires building power sats for $800 a kW or less. The rectenna estimate is $100-200/kW based on inverters costing $60/kW (same as PC power supplies which have the same parts). We can spend $600-700 per kW on parts, lifting them to GEO and assembly.

If you assume 2kg/kW power sats, then we can spend $300-350 a kg to buy parts, lift them to GEO and install them. At 4kg per kW, (the upper end of the power sat mass range) we can spend $175 per kg for parts and transport. Assuming 4kg/kW, $75/kg for parts (perhaps solar cells) and installation leaves $100/kg for transport.

Next: Hundred dollars a kg (cost to GEO)