Ecology: Biology of Interactions. 6.07. The Energy Supply Problem
The potential power of renewable energy sources is approximately 10-13 TW (terawatts, billions of kilowatts), which is of the same order of magnitude as humanity's needs.
Ukrainian (latest version) / Russian (updates discontinued) 6.06. The Pesticide Problem
D. Shabanov, M. Kravchenko. Ecology: Biology of Interactions Chapter 6. Human Ecology and Nature Protection
D. Shabanov, M. Kravchenko. Ecology: Biology of Interaction Chapter 6. Human Ecology and Conservation
6.08. Water Availability and Soils in Ukraine
6.07. The Energy Supply Problem In 1983-84, the UN General Assembly established WCED (the World Commission on Environment and Development), also known as the Brundtland Commission, after its chair, Norwegian Prime Minister Gro Harlem Brundtland. In 1987, this commission presented the report "Our Common Future," dedicated to prospects for civilization's development at the end of the 20th and in the 21st century. The potential power of renewable energy sources is about 10-13 TW (terawatts, billions of kilowatts), which is of the same order as humanity's needs. During preparation of the WCED report (1987), around 2 TW was being used, i.e., 21% of global consumption; of this, 15% came from biomass (firewood and agricultural waste), and 6% from hydropower. The use of firewood as an energy source can no longer increase and should decline. Renewable energy sources: — river-flow energy (solar energy transformed by the hydrological cycle) is used the most, yet still insufficiently; its expansion comes at the cost of ecosystem destruction and resettlement of people in flooded zones, release of toxic gases from flooded organic matter, spread of diseases such as schistosomiasis, barriers to movement of fish and terrestrial animals, and risk of disasters if dams fail; — wood burning can no longer rely on natural forests and requires dedicated cultivation of fuelwood within agrosystems; wood combustion pollutes the atmosphere, and release of pesticide residues with smoke is especially dangerous; — combustion of biomass-derived fuels; entails release of several toxic substances into the environment and requires technological development (in 1984, Brazil replaced 60% of gasoline with ethanol from sugarcane, producing about 10 billion liters; when oil prices dropped, this activity ceased to be profitable); — use of solar energy for heating and electricity generation is a highly promising sector whose development is constrained by the relatively high cost of necessary materials; "Some difficulties in the use of solar energy are, surprisingly, injuries from falls off roofs during maintenance and repair of solar installations, and damage caused by their dazzling glass surfaces" (Report of the UN World Commission on Environment and Development, 1987). — wind energy use is one of the oldest and most promising methods (a substantial share of energy in the Netherlands is generated by wind turbines); trade-offs include noise and vibration and withdrawal of part of the land area; — use of geothermal energy is possible in some regions and is currently developing intensively; — other sources (tidal power plants, use of natural temperature gradients, etc.). When renewable energy is used, no additional heating of the biosphere occurs, because energy merely changes form; their use does not lead to thermal pollution. There is a thermal limit for use of non-renewable sources, about 100 TW (still far away, but at current growth rates it would have been reached by the middle of the 21st century). In 1900, Rudolf Diesel presented at the Paris World Exhibition an engine running on peanut oil. Today, technology for producing biodiesel from soybean and rapeseed oil is considered promising; it can be used either pure or blended with petroleum products. Vegetable oils are esters of fatty acids with the triatomic alcohol glycerol. Replacing glycerol with monohydric alcohols (methanol or ethanol) yields biodiesel—a fluid yellowish liquid with the smell of popcorn or fried potatoes. 6.06. The Pesticide Problem
D. Shabanov, M. Kravchenko. Ecology: Biology of Interactions Chapter 6. Human Ecology and Nature Protection
6.08. Water Availability and Soils in Ukraine
6.08. Water Supply and Soils in Ukraine