Noeline Gannaway

Solar and renewable energy technologies - here defined as photovoltaics (PVs), solar-thermal, wind and biomass - are being used successfully in small-scale applications on a commercial basis and for some larger-scale power generation projects. For developing countries in particular, solar energy is an environmentally attractive and generally abundant resource, with enormous economic promise.

Solar energy is capable, in principle, of supplying five to ten times the total electricity demands of developing countries today while occupying land areas less than are currently used by hydroelectric projects. (The land requirements of biomass projects for electric power generation are larger, however, and are comparable with those of hydro)

Some of the solar thermal plants in California were built in as little as 9 months, and PV systems can be installed in even shorter times. For wind, times typically quoted are similar to those for solar thermal lead times - for biomass-fired power generation projects are likely to be longer, however, unless they are based on residues or high-yielding crops. In addition, the modularity of solar installations may allow for "line" maintenance, which should improve performance and reduce costs. A final advantage is the comparative ease and speed of decommissioning outworn plants. For practical purposes, the technology is "reversible".

Recent technical developments and reductions in the costs of solar energy technologies have been substantial. In the industrial countries a "luxury" market has arisen, and experiments show that PVs can be used effectively as a source of supplementary grid power. In developing countries, applications include village and domestic lighting, water pumping, battery charging, and supplying rural clinics. In Kenya, some 20,000 rural households get their electricity from solar energy - more than are served by the official rural electrification grid.

Because of the abundance and promise of solar energy, Dennis Anderson, senior adviser in the Industry and Energy Department of the World Bank, advocates that the development of solar technologies be speeded up. He recognises that this will require the combined and collaborative efforts of many parties - the developing countries themselves, along with private industry, the electric utilities, the energy research community, government departments of energy and development aid, private and public financing institutions, and non-governmental organisations.

Source of Finance

Since the Global Environment Facility (GEF) set up by the UN and administered by the World Bank, moved from its pilot phase to a permanent operational footing, in March 1994, it is now well placed to support an expanded programme of near-commercial applications of tested technologies and to attract substantial financing from public and private resources. Finance is now available from several sources. This could finance a very substantial programme of solar-thermal plants.

Developing countries have expressed much interest in the applications of solar energy, and some project preparation activity can be found in most countries, although on a small scale. Favoured areas are the use of wind as a supplementary power source and of PV for lighting, pumping and electricity supplies for clinics and schools in rural areas. Such applications can be found in several countries in Africa, Latin America, and Asia. Preparatory work has also been done for solar-thermal projects in Mexico, Morocco, Jordan and India. In Indonesia, a project to electrify remote communities using hybrid schemes based on wind and PVs has recently been prepared.

While a pipeline of projects is beginning to emerge, the amount of preparatory work being undertaken falls short of what is needed to draw effectively on available sources of finance.

Research and Development

Most solar energy R and D has been undertaken in the industrial countries, although some developing countries such as India, Brazil, and China have begun work.

New or developmental features in solar energy technologies could include improvement in competent design in PVs; new materials and cell design for PVs; improvements in operating temperatures and in thermal cycles of combined gas-fired, solar-thermal power plants; use of high-yielding annual crops and advanced gasification technologies for biomass-fired power plants; more advanced designs of wind-power projects; use of thermal-solar and wind projects to complement hydropower in the dry seasons; and new storage technologies for PVs, wind and solar-thermal power. Also recommended is R and D into efficient end-use technologies, which in lighting, heating and cooling frequently make solar energy more economically attractive. Examples are lighting with high-efficiency lamps, experiments with dish-Stirling systems for cooling and refrigeration, and the use of solar-thermal systems for treating toxic wastes.

Mention should also be made of R and D in transport technologies. The industrial countries are researching electric vehicles powered by batteries, fuel cells, and hybrid systems. At present this work may be best left to national programmes.

However, there is good economic reason for R and D to have an international dimension. The global warming problem means that if developing countries are to participate in policies to reduce carbon emissions over the long term, then bearing in mind their emerging demands for commercial energy - prospectively five or more times those of the industrial countries today - there will need to be a supply of non-carbon technologies with lower costs and improved performance becoming available, and tested and demonstrated locally.

Further analysis is needed to identify the next organisational arrangements. Possibly a consultancy group or a forum that would facilitate bilateral collaborations. An important part of the role of such a group would be to foster international collaboration on solar technologies by widening the awareness of developments through education, training, seminars, and sharing of the experiences of existing projects.

Source: The ESMAP Connection, Dec 1994.