Page 161 - Applied Photovoltaics

60 MW p of photovoltaic cells were produced for consumer products (Maycock, 2003)
but, in reality, the electricity actually generated would be less than 1% of this figure
(and not much more, even if used outdoors). Hence most PV statistics do not include
these products. The International Energy Agency (IEA) PV statistics, for instance
(www.iea-pvps.org), record only modules larger than 40 W p .

8.8 BATTERY CHARGERS
Where rechargeable batteries are already used as a power source, solar modules can
be used to keep the batteries fully charged during periods of reduced use,
compensating for self-discharge. This is already a common application on yachts and
recreational vehicles, but may be used increasingly for laptop computer, tractor and
car batteries.

Charging regimes are often important and careful notice should be taken of Section
6.7.2 on regulators, particularly with reference to self-regulation scenarios.

8.9 PHOTOVOLTAICS FOR DEVELOPING COUNTRIES
About 40% of people in developing countries do not have access to electrical power
(Martinot, 2003; Goldemberg et al., 2000) although small battery-operated appliances
are used in some locations, with consumers travelling to central battery recharging
facilities as necessary. In remote and inaccessible regions, supply of fuel and
maintenance services for diesel generators is also difficult. There is therefore a
potentially enormous market for photovoltaic-based systems, particularly for such
items as (Shepperd & Richards, 1993):
x household lighting, including PV lanterns
x household power
x TV and radio for education and entertainment
x communication systems
x water purification for drinking
x water pumping for irrigation and domestic water
x lighting and household power
x refrigeration of medicines and vaccines
x village battery charging stations
x wireless telephony
x community facilities
x productive activities.
Each of these can be designed as a stand-alone photovoltaic system, with village
systems supplying multiple uses. The IEA PV Power Systems Programme has
operated a specific developing country task (IEA PVPS, 2003).

Photovoltaics is particularly attractive because of its high reliability, non-dependence
on fuel supplies, long life and low maintenance (Eskenazi et al., 1987). However,
some level of continuing support, education and training of users is necessary to
avoid a high incidence of system failures (Lloyd, 2000), although these aspects are
now better managed than in the past (Bushlight, 2004; Wade, 2003a, 2003b). In
addition, the modular nature of photovoltaics allows small or large systems to be

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