Yes. One proposal I saw (a while back) for intercontinental power transmission in fact involved beaming it via one or more passive orbital reflectors. In other words, it's implicit in any technology that would enable practical SPS that intercontinental power transmission would also become practical, and at some significantly lower requirement for on-orbit hardware mass and complexity.
Henry On 3/17/2015 12:42 AM, Bill Claybaugh wrote:
The guy who wants to build solar power satellites thinks power can not be shipped across an ocean. Really? Bill Sent from my iPhone On Mar 17, 2015, at 2:59 AM, Keith Henson <hkeithhenson@xxxxxxxxx> wrote:On Mon, Mar 16, 2015 at 10:08 PM, Jim Davis <jimdavis2@xxxxxxxxxxxxx> wrote:Keith, 1. You seem to be deliberately avoiding the term specific impulse in favor of exhaust velocity. Any particular reason for that?I just got out of the habit. Done an awful lot of calculation for beamed energy and it was less trouble to use exhaust velocity to calculate the energy consumption of the engines. Factor of ten is within 2%/2. Am I reading that graph on page 2 correctly? If Skylon makes "only" a 100 flights per year the cost to LEO is over $5000/kg?That's what the graph from RE says. If you build these things at all, you need a large space traffic model for them to make sense. Like a power satellite construction project. snipFrom: Ian Woollard <ian.woollard@xxxxxxxxx>snipAnother type of power is peaker plants; those are used when the network needs extra power, and they're often highly inefficient, but they can command more than ten times the price per kilowatt. They run only a small fraction of the time.In the long run, power satellites should cost less than peaker plants. So it makes sense to build out power satellites to peak demand, in fact well beyond peak demand. Instead of managing the grid by generation, in the future we could manage it by load. Any available power between current load and the capacity of the power satellites would be diverted into electrolysis plants to make cheap hydrogen. We can use the hydrogen and CO2 salvaged out of the air to make synthetic hydrocarbons. The energy to make the hydrogen for a bbl of oil is 20 MWh. The capital cost (based on the Sasol plant in Qatar) is around $10/bbl. So one cent power would make $30/bbl synthetic oil, 2 cents would make $50/bbl etc. Solves both the fossil fuel problems.From: Bill Claybaugh <wclaybaugh2@xxxxxxxxxx>(Keith)How do you reduce base load? Base load feeds streetlights, domestic water pumping, sewer pumps, refrigerators and critical infrastructure. Shut it off at night and some people will get up the next morning knee deep in sewage.With storage and interconnection: I assume storage is obvious; connecting U-rope with the Arabian peninsula--where the Saudi's and Oman plan to use the oil to build vast solar plants--extends the effective "daylight" period. Ultimately, connecting the future Arab, European, and North American grids will provide more than sufficient supply for the small nighttime load.The cost for sending power long distance is substantial, around a cent per kWh per 1000 km. Plus as others have pointed out, there is no way to get it across an ocean. Keith