Welsom Space Consortium: Solar Space Power From Megawatts to Gigawatts

New lightweight material for collecting solar power and deploying the solar collectors could radically increase the solar power that could be delivered in one rocket launch. The Welsom Space Consortium has several interesting presentations and plans for scaling up space based solar power.

Carbon Fiber Reinforced Plastics (CFRP) booms are already 20 meters long and 50 meter and 150 meter booms are being designed and studied. The CFRP booms deploy linearly with a slow, controllable speed of about 1 meter per minute. This deployment technology has been demonstrated by deploying a 400 m**2 (20 m square) solar sail in a vacuum environment at the NASA Plum Brook Facility. The technology is envisioned to provide a highly reliable rigidization structure for future space systems requiring large areas in excess of 100 m**2.

Laboratory test cells have been produced by Institut de Microtechnique at the University of Neuchatel, Switzerland using LaRCTM-CP1 thin-film substrates produced by SRS Technologies in Huntsville, AL that have the highest power/mass ratio on record – 4300 W/kg If a-Si:H cells can be deposited over large surface areas onto fluorinated polyimide LaRC CP1TM films, then these should have similar power densities. Allowing generous losses for support equipment, cell gaps, and power losses, a gross power density in excess of 1200 W/kg should be readily achievable.

The largest dedicated space solar cell manufacturer has a 1 Megawatt production capacity.

A project has been proposed to design, manufacture, and ground test a breadboard array which combines the Kayser-Threde/DLR deployment concept and advanced thin-film solar cell technology developed by the Institut de Microtechnique. This project will assess the compatibility of the KT deployment and membrane stowage concept with the CORIN/a-Si:H solar array materials. It will also perform functional, as well as environmental, tests on the breadboard model.

An early space qualification test would then demonstrate the atomic oxygen and radiation resistance in space, using 20-meter square arrays, which should generate 12.5 kW of power with a total mass on the order of 10 kg.

With deployable arrays with a specific mass above 1 kWe/kg, 1 MWe would have a mass of 1 tonne or less. It therefore appears quite feasible to produce space arrays in the multi-megawatt range. A standard solar array unit would be about the size of the 20-meter Scalable Square Solar Sail System which was produced by SRS Technologies. This array is 20 meters square, for a total area of 400 m2. Such an array should produce at least 50 kWe with a mass of 40 kg. A 100 MWe power plant would require 2,000 such arrays, for a total array mass of 80,000 kg. A deployable 20 m x 20 m array has also been built for a space demonstration by Kayser-Threde.

European space tower with 150 meter boom sections put together into a 15 kilometer long tower. Delivers 275 MWe to the ground.

Space solar power could transmit laser light to a ground based solar farm to match typical electrical load in an area and remove the need for power storage for solar farms.

Space Qualification of Welsom Ultra-lightweight CFRP Boom TFSC Space Solar Arrays as Sub-Arrays of the 1.2 MW Space Array ready for Launch by 2012.

Key to locally rational decisions that bring about the Distributed Energy Solar Economy and Space Space-Based Solar Power are four fold:
1.) The the technologies to be developed must have applications that are nearer term and multi-faceted.
2.) Interim systems must provide value to the decision-makers/investors within both government and industry that also provide income for sustained market expansion and sustained growth of manufacturing capacities.
3.) Space-Based Solar Power pilot projects must be affordable, have value and
retire risks while providing legitimate Energy and Wireless Power Power Transmission services.
4.) Space-Based Solar Power must maintain current energy production gains
while expanding manufacturing for Space Space-Based Solar Power to provide
Sustainable Carbon Neutral Energy Generation at Terawatt levels.

FURTHER READING
Kevin Reed who heads the Welsom Space Consortium pitched Palau on low altitude space based solar power system

The test satellite will be situated in a low ‘Molniya’ orbit and will pass over a number of islands during a daily cycle. The plan is to have one base station connected to the grid on Helen Island, and an additional one thousand handheld rechargers distributed among the populace. “They can use them to power their cellphones or laptops,” Reed says. “The amount of power required is very minimal, something like 2 watts.”