Space Power is about the generation of power from space.

The space around Earth is filled with intense sunlight, undiffused by atmosphere, continuously. It represents an inexhausible supply of energy that can be converted to electricity using semiconductors - that is without the use of any moving parts.

A small fraction of this energy could supply a large part of the world's future energy requirements for the foreseeable future. In addition, it could do it without the need for any kind of fuel, and without producing any waste product.

All that's needed is large-area collectors - and that means large, thousands of square kilometers - and a way to transmit the collected power down to Earth. Several different methods are possible, but the one that has received the most effort so far is the use of microwave beams or wireless power transmission.
29 July 2012
Added "Space Debris and Its Mitigation" to the archive.
16 July 2012
Space Future has been on something of a hiatus of late. With the concept of Space Tourism steadily increasing in acceptance, and the advances of commercial space, much of our purpose could be said to be achieved. But this industry is still nascent, and there's much to do. this space.
9 December 2010
Updated "What the Growth of a Space Tourism Industry Could Contribute to Employment, Economic Growth, Environmental Protection, Education, Culture and World Peace" to the 2009 revision.
7 December 2008
"What the Growth of a Space Tourism Industry Could Contribute to Employment, Economic Growth, Environmental Protection, Education, Culture and World Peace" is now the top entry on Space Future's Key Documents list.
30 November 2008
Added Lynx to the Vehicle Designs page.
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A Very Big Chip

This is the word that is starting to be used for the growing business of making and using solar cells for energy production. Solar cells (or photovoltaic cells) are semi-conductors - they're made of wafer-thin layers of silicon and other materials - which means they have the advantage that they use very little material, and operate without moving parts.

A matter of scale

The major difference between solar cells and micro-electronics is their area. Solar energy in space near the Earth has an intensity of about 1.4 kW per square meter. Near the equator on Earth it's about 1 kW/sqm at mid-day, and at higher latitudes it's typically about 500 W/sqm. So to collect large amounts of energy you need large areas of solar cells. For example, a million kW, one Gigawatt (GW), which is enough for about 1 million people at the rich countries' level of consumption, would need about 1 square kilometer of desert near the equator at mid-day if the efficiency was 100%.

Quantity not quality

However solar cells' efficiency is about 10% - it varies from about 5% to about 20% according to the type of cell. So in fact about 20 square kilometers would be required for 1 GW. Thus to supply electric power for hundreds of millions of people, which is necessary if solar cells are to supply a significant share of world energy needs, thousands of square kilometers of solar cells will be needed - "macro-electronics". Although this sounds a lot, there will be no problem in producing such large quantities of solar cells, once the costs are competitive with other energy sources, because the amount of material used is so little.

Luckily, the semi-conductor industry is the most dynamic field of manufacturing industries. Technological innovation is racing along as fast than ever, and the cost of solar cells has been falling for years.

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