====== ENERGY COLLECTORS ======
Energy collectors gather energy from natural sources.
Man has used solar power since prehistory to preserve
herbs, vegetables, and meat by drying them in the sun.
Today, major installations may use hydroelectric, solar, or
geothermal power, but solar power is the most common
means of portable energy collection.

=== Windmills (TL5) ===

In the 19th century (TL5), many farms in windy areas
used windmills. They were common in the U.S. Midwest
and Great Plains to pump water from deep wells into holding
tanks or ponds. At TL6+, a windmill or wind turbine
produces electrical power; in a good windy site, it can provide
external power to a small household or workshop. Of
course, it provides no power on calm days! $10,000, 500 lbs.
LC4.

=== Hydroelectricity (TL6) ===

At TL5, waterwheels simply provide mechanical energy
to drive millstones, saw blades, trip hammers, bellows, etc.
At TL6, however, hydroelectric plants begin to convert
mechanical energy into electricity. At TL8, a waterwheel or
a small water-powered turbine can provide external power
to a single household in an area with a fast-flowing, yearround
water source; a small hydroelectric turbine suitable
for the purpose is $10,000, 250 lbs. LC4.

=== Solar Panels (TL7) ===

Solar panels convert sunlight into electricity. They might
power homes here on Earth . . . or satellites and robots on
distant planets. Current panels are made of layers of plastics,
and are strong, lightweight, and flexible. They can even
be incorporated into such items as roofing shingles. They
provide power only in sunlight, however. In any environment
dim enough to give even a -1 Vision penalty, they produce
no power.

Solar Power Array (TL7). A large array of solar panels
capable of providing external power to a whole household.
It covers a sizable portion of the roof of a family sized
dwelling. $25,000, 1,200 lbs. LC4.

Solar Powered-Battery Recharger (TL8). This flexible,
portable solar panel can be rolled up like a tarp and stuffed
in a backpack. In good sunlight, it can power a hand-held
device or recharge a handful of batteries in a few hours.
$100, 2 lbs. LC4.



=== Solar Panels (TL9) ===

Solar panels convert light into electricity. They work in any environment where strong light (such as sunlight) is available. The primary development at ultra-tech TLs is in inexpensive production of thin-film solar cells.

Solar Power Array (TL9) : This semi-portable array of solar panels is a generator that provides external power. It takes a minute to deploy, and covers about 400 square feet. $5,000, 250 lbs. The size assumes an earthlike level of sunlight; multiply cost and weight by relative light levels for other environments. LC4.

Solar Paint (TL9): These cheap plastic solar cells can be painted onto any surface, including clothing or rooftops. A coating of solar paint is only 20% of the cost and weight of regular solar panels, but it requires twice the surface area and has no DR. LC4.