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x Do not use electricity for cooking (other than small appliances and
microwave ovens), hot water, space heating, clothes drying or air-
conditioning. Many less expensive alternatives exist.
x Electric refrigerator-freezers are borderline cases, but can be used, provided
highly efficient models are selected.
In many countries, new appliances, particularly refrigerators, freezers, dishwashers,
air conditioners, washing machines and clothes dryers receive ‘energy ratings’,
making it easier for consumers to select efficient appliances. Sometimes, regulators
require labelling to allow consumers to make informed choices between competing
products and/or products are required to meet regulated standards for energy
efficiency. In Australia at present, clothes washers, clothes dryers and dishwashers
have mandatory energy labelling; air conditioners, refrigerators and freezers require
labelling and need to meet minimum standards and water heaters, electric motors,
lamps, ballasts, transformers and commercial refrigeration have minimum standards
without a labelling requirement (Australian Greenhouse Office, 2004a). A list of
Australian Standards for energy efficiency is also provided at the above web site.
Power used by equipment left for long periods on ‘standby’ is an underappreciated
load (Australian Greenhouse Office, 2004a) that should be minimised in RAPS
situations.

9.1.1 The choice between AC and DC
Grid-connected households use AC power for virtually all appliances. For RAPS
systems, however, this may not be the most cost-effective choice. DC appliances are
commonly more efficient and avoid the need for an inverter, with its associated loss.
However, DC wiring is heavier duty, requires special switches and may need
specialised personnel for installation. In addition, a much smaller range of DC
appliances is available and their smaller market usually makes them more expensive.
A combination of AC and DC wiring has advantages when considering the range of
available appliances and their relative efficiencies, but may introduce safety problems
and complications during maintenance. Care should be taken to meet the relevant
local standards (Standards Australia, 1999–2000a, 1999–2000b, 2002). Several
countries have accreditation processes for system designers and installers that
produce a body of qualified people who are aware of industry best practice standards
and all relevant national standards. In Australia, this is administered by the Australian
Business Council for Sustainable Energy (BCSE, 2004).

9.1.2 Appliances
(See Pedals, 2003; Australian Greenhouse Office, 2004a, 2004b, Castañer et al.,
2003; Lawrence Berkeley Laboratories, 2004.)

Lights
Fluorescent lights are about four times more efficient than incandescent lights and
should be used with RAPS systems (Ball & Risser, 1988). Modern electronic ballast
AC fluorescent lights and also DC fluorescent lights are superior to the older style
fluorescent lights. Most incandescent lights that are operated for a few hours per day
can be cost-effectively replaced with compact fluorescents (Castañer et al., 2003).

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