Alternative energy

windgenerators (pigott) brew.

pedal generators

car alternators often used but they are not ideal, they give no voltage at low speeds and so needs gearing, can use belt from tractors. UK supplier for the tractor belts

tims pedal generator using dc motor and cycle training stant dc motors ideal and can be bought new but are expensive car windscreen wiper motors could be used. as they are also dc motors. need to regulate the voltage.

stepper motors. from printers etc will give power at very low speeds. interesting to play with leds and turning the motor by hand. they have multiple sets of coils.

Solar panels

Maximum power point tracking (mppt) regulators are the more efficient but expensive. Normal regulators will allow the battery state to determine voltage which may not be the most efficient for the panel. MPPT regulators use a control circuit to 'search' for the voltage allowing the highest power output.

note that with the right regulator it is also possible to charge 12v battery from 24v panel (morningstar sunsaver mppt) or a 24v battery from 12v panel (emponi sol1)

for situations where you do not have enough power to use an electric soldering iron, a gas powered soldering can be used (they take expensive little cartridges). another solution could be just to heat nails in a fire and use pliers to hold them.

batteries

it is possible to use old car batteries which no longer will charge to 12v (which you often find discarded) as 9v batteries, which can power, for example, 3 led bike lights soldered together in series (2xAAA batteries=3v).

gel cells

12 volt gel cell charger plans

Thermoelectrical generators

Small heat powered electrical generators that can be attached for example to a wood burner. They dont produce a lot of power but could be useful for electronics stuff

• thermoelectrical generator wikipedia article
• thermalforce.de site selling them
• video of TEG

Other stuff

Power over ethernet would be usefull for data radio projects