Energy – nothing works without it
In addition to reliable water supplies and wastewater disposal systems, environmentally acceptable energy supplies are another fundamental prerequisite for improving living conditions in the emerging and developing countries, and for growth and prosperity in the industrial nations.
The reason for the disproportionately high increase in energy consumption in recent decades and for the forecast of a steep rise in the new century is the enormous backlog demand existing in the emerging and developing countries. Today, just 20% of the world’s population consume 80% of the primary energy, while the remaining 80% of the population consume a mere 20%.
One-third of humanity still has no access whatsoever to modern, reliable and affordable energy supplies. Despite the prediction made by the Club of Rome in 1972, there is still no sign of our reserves of crude oil and natural gas being exhausted in the first few decades of the third millennium.
Increasingly sophisticated exploration methods have led to the constant discovery of new deposits and larger resources. New extraction techniques, e.g. in the offshore sector, have substantially improved the yield of known deposits. The impending shortage of primary energies has thus receded into the second half of the new century.
The well-founded concerns about environmental pollution and the rising price of primary energies compel us to save energy and improve efficiency, both when consuming primary energy and when converting it into secondary energies, such as electricity. The tapping of renewable primary energies, such as hydropower, solar and wind energy, biomass and geothermal energy, can help to make our energy stocks last and reliably cover the increasing energy requirements of a growing global population in an environmentally friendly manner.
Great hopes were attached to the introduction of superconduction in the field of energy generation and distribution engineering, particularly in connection with generators and transformers. Progressing towards a target year of 2050, the leading industrial nations are working on nuclear fusion, a virtually CO2-neutral, and thus environmentally compatible and almost inexhaustible source of energy.
Hydropower and wind energy
The expansion of hydropower and wind energy takes first and second place today when it comes to alternative or renewable energies. Thanks to their time-proven technology, the various types of hydroelectric power station in operation are a sure guarantee of reliable energy supplies that are capable of meeting all the requirements of the utility companies and consumers alike, from the base load to peak loads. A slight emission of methane only occurs at times during the banking up of water in the headwater and tailwater areas.
After two decades of trials, wind turbine facilities, the majority of which are still installed in rural areas, deserve a similarly positive rating today. However, due to emerging resistance on the part of local residents, an increasing number of offshore wind farms will be built in future. While this entails higher investment and maintenance costs, offshore facilities do not constitute a nuisance either to the eyes or to the ears.
Solar energy and biomass
The exploitation of solar energy using thermal collectors is already a reality for heating water in many parts of the world. The really ideal process of generating electricity directly by photovoltaic means is still in the trial stage, owing to the relatively high investment costs and difficulties with the long-term viability of the solar cells in real weather conditions.
Biomass and its direct incineration or lowtemperature carbonization to produce gas are being used with success, albeit to a very limited extent particularly for the recovery of waste products from agriculture, forestry and the wood-working industry for the provision of CO2-neutral energy supplies. These relatively small plants can already serve today as an alternative to gas-fired cogeneration plants for decentralized generation of electricity, heating and cooling.
In base-load operation, these plants suffer from corrosion and noxious exhaust gases as a result of the fuel used. Both of these problems cause higher expenditure for the operation, maintenance and repair of the facilities than originally assumed in the economic efficiency calculations drawn up in the project planning phase.
The same problems arise in connection with refuse-fired combined heat and power plants and low-temperature waste carbonization plants. These operate according to various principles and utilize household, commercial and industrial waste. Up to now, the lowtemperature carbonization process, and also pyrolysis and gasification processes, had dashed the hopes set in them, owing to complications arising under the harsh conditions of everyday operation associated with the difficulties of using waste as a fuel. In contrast, the latest waste incineration plants have advanced firing systems and flue-gas-cleaning equipment that meet all the demands on environmentally friendly operation. They produce non-harmful residues that can be re-used and only very small quantities of toxic incineration residues that need to be disposed of as hazardous waste.
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