Energetická nouze vede Kubu k využití biomasy
Alternatives to oil
The cutoff of Soviet oil has forced Cuba to enact an emergency conservation program as the nationÆs annual oil imports have plunged from 13,000 tons to 6,000 tons in the last few years since the severe reduction of trade with the formerly socialist countries. The government has contingency plans to keep the country running on as little as 4,000 tons annually. Government officials view conservation, biomass, mini-hydro and solar project not solely as emergency measures, but as permanent alterations in the countryÆs energy production mix.
The most visible sign of conservation is the ubiquitous bicycle. There are now 800,000 bicycles in Havana alone, most purchased from China . Cuba will soon produce bicycles domestically, and they are expected to be a principal form of local transportation well into the future.
Almost 30 percent of CubaÆs energy supply now originates from biomass. Of CubaÆs 160 sugar mills, 104 are totally powered by their own bagasse, a by- product of sugar production. In addition, waste fiber is used to make paper and other products. The process, however, deprives fields of the harvest detritus that has traditionally played an important fertilizing function. Farmers have partially solved this problem by reconstituting the plantsÆ waste water and returning it to the fields. The agricultural sector is also making heavy use of animal manure.
Hydrological sources of energy are limited, but small hydro projects, built with assistance from a German church-based organization, provide electricity for some isolated mountain communities.
Although Cuba harnesses little solar energy, the abundant sunshine it receives makes the island a good candidate to develop a vibrant solar industry. Now, prompted by the oil shortage, the government has established a Solar Institute in Santiago de Cuba. The Institute has primarily been engaged in small-scale projects such as water heating.
Unfortunately, Cuba is also continuing to develop non-renewable energy projects. It is constructing a nuclear power plant and undertaking a joint project with a European consortium to explore for offshore oil. CubaÆs illusions about the safety of nuclear energy were shattered by the disaster at Chernobyl, particularly since children affected by that accident were brought to Cuba for medical treatment, but the desperation caused by the oil crunch is so severe that the government is going ahead with its nuclear power plant plans anyway. Juan Antonio Blanco, professor of international relations at the University of Havana, describes CubaÆs resort to nuclear energy as being \"like chemotherapy for a cancer patient. When it is a matter of survival, one takes the risk.\"
The price of pesticides
As the examples of forest and energy policy illustrate, the pervasive economic crisis intersects with environmental issues in a wide variety of ways. In some areas, it has actually led to a strengthening of environmental policies.
o The economic crunch put an end to revolutionary CubaÆs large-scale, centralized agricultural systemÆs intensive use of pesticides and chemical fertilizers. The lack of funds to purchase chemical pesticides and fertilizers on the world market made the move to organic farming more urgent. Farmers are replacing pesticides with biological controls, and reductions in chemical fertilizer are slated to continue, according to Ferrer, \"to an ultimate goal of phasing chemicals out entirely.\"
Farmers are returning to more traditional and sustainable practices. A previous drive to replace farm animals with tractors has been reversed. Dairy herds are being built up as part of the effort to make Cuba self-sufficient in food. Farmers are also experimenting with newer methods such as using manure in the production of biogas and to help breed a worm that in turn is used for animal feed.
o The Cuban recycling experience contrasts dramatically with U.S. practices, where local government recycling usually comes only in direct response to the loss of landfill sites, reinforced by a growing public awareness, and is marred by lack of industry use of what has been collected. Recycling is far better organized and more nearly complete in Cuba, where the population now mines the waste stream for any useful material. From banana peels to toothpaste caps, everything possible is reused.
But in many other cases, the economic crisis is limiting the ability of the government to enact environmental programs, or leading it to pursue environmentally risky economic policies.
o CubaÆs efforts to build up its tourism industry as a means to generate foreign currency pose a number of environmental threats, but after some unpleasant lessons, the government is now working carefully to mitigate them. A causeway built as part of the tourist development of the Key islands off the countryÆs north coast interfered with the circulation of the water in the Straits of Florida which in turn depleted the fish habitat and caused mangrove trees to die. Once the case against the causeway was made, however, the government responded quickly: it removed a major span and replaced it with a bridge. Now interdisciplinary teams are doing baseline studies to determine the amount of development the Keys can sustain without losing their environmental integrity. These studies will determine the type and extent of hotel building and construction of other tourist facilities that will be permitted.
o The government is working to clean up the polluted Havana Bay, and is cracking down on industrial managers responsible for its contamination. For example, the government ordered managers of a fertilizer plant which was dumping waste into the harbor to change their operating practices. After failing to comply, they were charged with negligence, tried and are now in prison.
But the governmentÆs clean-up efforts are hampered by lack of funds for a major overhaul of the cityÆs sewer system, built in 1902. The problem is less severe in newer sections of the city that were constructed with their own systems. The most advanced system is a housing project called Las Arboledas, which is currently being built. The end- products of sewage treatment will be water, usable for irrigation of the individual and community gardens which are now a feature of the Cuban urban landscape, and sludge, which is safe for fertilizing the gardens. Architect Gabriela Gonzalez acknowledges that there is a cultural barrier to the use of the sludge, which he hopes will be overcome by education and experience.
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