Edited by Rachel Duncan 4th Edition ISBN 0-907649-91-2 London ...

72 RGS-IBG Polar Expeditions Manual
For your fixed radio or communications equipment you should consider using a
leisure battery as used in caravans. Alternatives such as car batteries are designed for high
current discharge and rapid recharging and may not provide the output or recharge
properly with solar cells or wind turbines.
Leisure batteries are designed for the sometimes intermittent nature and different
rates of field charging. Low maintenance or sealed (but vented) types are preferred. They
have often the electrolyte in a safer gelled form, eliminating the risk from acid spills even
if the battery is inverted.
Beware in all cases of potentially explosive battery gas build-up in confined spaces
whilst charging. Beware also of disconnecting power leads from batteries under load or
charge, as the gas given off in the charging process can be ignited by such sparks, causing
a nasty explosion. One accident of this type in Antarctica sadly resulted in the loss of sight
for an expeditioner.
7.5.3 Generators
If higher voltage or current requirements are needed, portable generators may be selected,
though the transportation weight of the generator and restrictions on fuel may preclude
their use.
Power outputs are available from a few hundred Watts up to tens of Kilowatts.
Voltages tend to towards either 220/240 volts or 110 Volts 50/60 Hertz AC. The lower
voltage is preferred for safety purposes and plugs/sockets are colour coded, Blue for
220/240 and Yellow for 100 Volts. DC charging voltages are often available
simultaneously – either 12 or 24 Volts are common with currents sometimes exceeding 15
amps.
7.5.4 Fuel
Gas powered – generators at low temperatures are not favoured due to low vapour
pressure.
Diesel – commercially available low temperature additives help prevent diesel or fuel oil
from ‘waxing up’. Starting at low temperatures without a heating element—such as a glow
plug—can be difficult, though once they are running diesels are easy to maintain and
operate.
Petrol – low temperature additives are available too; most help to absorb water in the fuel,
without which freezing of the carburettor can be problematic. Starting using a hand pulley
without the use of low temperature grease can lead to strained muscles. The engine oil
should be suitable for low temperatures.
Where possible—when not in use—a cooling shutdown generator should be moved
into a warm and dry environment, though rime and ice build up is likely when first moved
into such locations. When the generator has dried off and warmed up it can be, when
required, moved outside and started with some confidence.
Fuelling should be carried out externally, using a device to stop snow and ice
particles entering the fuel tank.