Page 303 - Applied Photovoltaics

x high water requirements for digester
x feedstock for digester may be scarce particularly in arid regions
x relatively high labour needs for digester operation
x relatively high investment costs in digester and gas storage equipment,
making it most suitable for larger systems.

F.10 SOLAR RADIATION, USED VIA PHOTOVOLTAICS
Advantages:
x energy resource is almost universally available
x high correlation between energy availability and needs
x low environmental impact
x reliable
x zero fuel costs
x long life
x low maintenance and running costs
x can be operated by unskilled labour
x suitable for systems of any size.
Disadvantages:
x sophisticated technology, not suited to local manufacture
x applications and balance of system components still under development
x high investment cost
x diffuse energy resource
x skilled engineers needed for maintenance
x output subject to solar insolation variations.

REFE RE NCES
Halcrow, W. and Partners and the Intermediate Technology Development Group Ltd
(1981), Small-Scale Solar Powered Irrigation Pumping Systems—Technical and
Economic Review, UNDP Project GLO/78/004, World Bank, London.

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