Assessment of evaluations of AID renewable energy projects : a search for cost-effective replicable technologies

projects. Special evaluation is based on review of project documents, especially evaluations and audits. Results varied widely. (1) Photovoltaic (PV) systems seem to be cost-competitive only for specialized uses (excluding water pumping) where electric power is costly or non-existent, e.g., isolated health clinics. Further, management and labor requirements could prevent widespread acceptance of PV units. (2) Conventional wind machines are feasible in certain cases (e.g., water pumping), but only if there is enough wind at the site. (3) Solar water heating, while limited in scope, is cost-effective, requires relatively little maintenance, and, if used widely, can have a quantifiable effect on energy problems. Other solar techologies have proven unpromising. (4) Given a suitable site and the necessary design, installation, and maintenance resources, small hydro can be a practical source of electricity and have a major developmental impact. (5) The need for long-term protection of the environment seems to make forestry plantations an essential option despite their cost and mixed success in A.I.D. projects. Due to the managerial problems they typically encounter, these projects seem to require qualified technical backstopping. They are often cost-effective when part of forestry schemes with larger economic and environmental goals. (6) Producer gas is cost-effective but requires maintenance and support services which outweigh this RET's limited, short-term benefits. Such projects are difficult to justify. (7) Household biogas and woodstove projects have generally not been successful except in countries (e.g., Nepal, India) able to afford the high level of maintenance and support required. Industrial and large-scale biogas projects should be delegated to the private sector. (8) Due in part to technical and consumer acceptability problems, early wood/charcoal stove projects were only modestly successful. More recent metal stove projects have proven more promising where supported by the private sector; such support is also important in fuelwood/forestry programs and would be useful in wind system maintenance. A key factor is the extent to which users can keep the stoves operational. Despite some notable failures, biomass fuel, wind, small hydro, and, more recently, gasification RET's have met crucial local needs for energy. The ultimate cost-effectiveness of these RET's is yet to be fully ascertained. Lessons learned are that: of all energy programs, fuelwood and forestry projects have the most organizational problems; a simple technology (e.g., solar dryers) can generate an impossibly complicated project; and project success depends on continuity and especially on the effective involvement of project staff and energy users.