3. Batteries and Cells
Zinc carbon Low current Low cost
suitable for
infrequent use
Zinc Chloride Medium current Medium cost
suitable for
regular use
Alkaline High current High cost
suitable for
regular use
Nickel cadmium Medium and high High outlay, low
(not low) current lifetime cost.
Rechargeable
4. Solar Cells
Powered by light Suitable for low High outlay, zero
energy current, low running costs
Most effective in voltage
sunlight applications
