Ńņóäīļåäč˙
rus | ua | other

Home Random lecture






Renewable Energy: A Viable Choice


Date: 2015-10-07; view: 593.


 

Renewable energy systems – notably solar, wind, and biomass – are poised to play a major role in the energy economy and in improving the environmental quality of the United States. California's energy crisis focused attention on and raised fundamental questions about regional and national energy strategies. Prior to the crisis in California, there had been too little attention given to appropriate power plant siting issues and to bottlenecks in transmission and distribution. A strong national energy policy is now needed. Renewable technologies have become both economically viable and environmentally preferable alternatives to fossil fuels. Last year the United States spent more than $600 billion on energy, with U.S. oil imports climbing to $120 billion, or nearly $440 of imported oil for every American. In the long term, even a natural gas-based strategy will not be adequate to prevent a build-up of unacceptably high levels of carbon dioxide (CO2) in the atmosphere. Both the Intergovernmental Panel on Climate Change's (IPCC) recent Third Assessment Report and the National Academy of Sciences' recent analysis of climate change science concluded that climate change is real and must be addressed immediately and that U.S. policy needs to be directed toward implementing clean energy solutions.

Renewable energy technologies have made important and dramatic technical, economic, and operational advances during the past decade. A national energy policy and climate change strategy should be formulated around these advances. Despite dramatic technical and economic advances in clean energy systems, the United States has seen far too little research and development (R&D) and too few incentives and sustained programs to build markets for renewable energy technologies and energy efficiency programs. Not since the late 1970s has there been a more compelling and conducive environment for an integrated, large-scale approach to renewable energy innovation and market expansion. Clean, low-carbon energy choices now make both economic and environmental sense, and they provide the domestic basis for our energy supply that will provide security, not dependence on unpredictable overseas fossil fuels.

Energy issues in the United States have created "quick fix" solutions that, while politically expedient, will ultimately do the country more harm than good. It is critical to examine all energy options, and never before have so many technological solutions been available to address energy needs. In the near term, some expansion of the nation's fossil fuel (particularly natural gas) supply is warranted to keep pace with rising demand, but that expansion should be balanced with measures to develop cleaner energy solutions for the future. The best short-term options for the United States are energy efficiency, conservation, and expanded markets for renewable energy.

For many years, renewables were seen as energy options that – while environmentally and socially attractive – ­occupied niche markets at best, due to barriers of cost and available infrastructure. In the last decade, however, the case for renewable energy has become economically compelling as well. There has been a true revolution in technological innovation, cost improvements, and our understanding and analysis of appropriate applications of renewable energy resources and technologies – notably solar, wind, small-scale hydro, and biomass-based energy, as well as advanced energy conversion devices such as fuel cells.

There are now a number of energy sources, conversion technologies, and applications that make renewable energy options either equal or better in price and services provided than the prevailing fossil fuel technologies. For example, in a growing number of settings in industrialized nations, wind energy is now the least expensive option among all energy technologies – with the added benefit of being modular and quick to install and bring on-line. In fact, some farmers, notably in the U.S. Midwest, have found that they can generate more income per hectare from the electricity generated by a wind turbine than from their crop or ranching proceeds. Also, photovoltaic (solar) panels and solar hot water heaters placed on buildings across the United States can help reduce energy costs, dramatically shave peak-power demands, produce a healthier living environment, and increase the overall energy supply.

The United States has lagged in its commitment to maintain leadership in key technological and industrial areas, many of which are related to the energy sector. The United States has fallen behind Japan and Germany in the production of photovoltaic systems, behind Denmark in wind and cogeneration system deployment, and behind Japan, Germany, and Canada in the development of fuel-cell systems. Developing these industries within the United States is vital to the country's international competitiveness, commercial strength, and ability to provide for its own energy needs.

Theoretically, renewable energy sources can meet many times the world's energy demand. More important, renewable energy technologies can now be considered major components of local and regional energy systems. Solar, biomass, and wind energy resources, combined with new efficiency measures available for deployment in California today, could supply half of the state's total energy needs. As an alternative to centralized power plants, renewable energy systems are ideally suited to provide a decentralized power supply that could help to lower capital infrastructure costs. Renewable systems based on photovoltaic arrays, windmills, biomass, or small hydropower can serve as mass-produced "energy appliances" that can be manufactured at low cost and tailored to meet specific energy loads and service conditions. These systems have less of an impact on the environment, and the impact they do have is more widely dispersed than that of centralized power plants, which in some cases contribute significantly to ambient air pollution and acid rain.

There has been significant progress in cost reductions made by renewable technologies. In general, renewable energy systems are characterized by low or no fuel costs, although operation and maintenance costs can be considerable.

Systems such as photovoltaics contain far fewer mechanically active parts than comparable fossil fuel combustion systems and are therefore likely to be less costly to maintain in the long term. Costs of solar and wind power systems have dropped substantially in the past 30 years and continue to decline. For decades, the prices of oil and natural gas have been, as one research group noted, "predictably unpredictable." Recent analyses have shown that generating capacity from wind and solar energy can be added at low incremental costs relative to additions of fossil fuel-based generation. Geothermal and wind can be competitive with modern combined-cycle power plants – and geothermal, wind, and biomass all have lower total costs than advanced coal-fired plants, once approximate environmental costs are included. Environmental costs are based, conservatively, on the direct damage to the terrestrial and river systems from mining and pollutant emissions, as well as the impacts on crop yields and urban areas. The costs would be considerably higher if the damage caused by global warming were to be estimated and included.

The push to develop renewable and other clean energy technologies is no longer being driven solely by environmental concerns; these technologies are becoming economically competitive. The traditional energy sector has lacked appeal to investors in recent years because of heavy regulation, low growth, and a tendency to be cyclical. The United States' lack of support for innovative new companies sends a signal that U.S. energy markets are biased against new entrants. The clean energy industry could, however, become a world-leading industry akin to that of U.S. semi-conductors and computer systems.

Using the information of the text, state whether the statements below are true or false, correct the false ones.

1. Before the crisis in California the issues of correct location of power plants and dealing with pick-power demands were not appropriately attended.

2. Imported oil for every American costs about $120 billion.

3. Clean energy solutions are crucial for the U.S. since natural gas-based national policy does not contribute into curbing the built-up of GHGs (green house gases).

4. Clean energy solutions do not provide the country's independence on unpredictable fossil fuel market.

5. “Quick fix” energy supply solutions are more politically than environmentally expedient.

6. Renewable energy technologies have become profitable.

7. Alternative energy sources are solar, wind, small-scale hydro, and biomass-based energy, as well as tide-wave energy.

8. Photovoltaic systems are the cheapest to install and bring on-line.

9. Hot water heaters can cut the needs of energy during rush hours, improve living environment, and increase the overall supply of energy.

10. The United States is the leader in the production of photovoltaic and fuel-cell systems.

11. Renewable systems based on photovoltaic arrays, windmills, biomass, or small hydropower are less economically and energetically efficient but more environmentally friendly than traditional power sources.

12. Environmental costs are estimated by the damage done to soil, water, wildlife and agriculture.

13. Alternative power industry may compete with semi-conductors and computer systems in the U.S.

4 (a). Watch the video fragment “Tidal Wave Alternative Energy” and fill the gaps in the following fragments from the script using the words and expressions in the box..

barrage, high tide, low tide, turbines, dam, tidal barrage, hydropower, potential energy.

 

Of the various technologies to capture the ocean's energy, a ____________ is the closest in design to traditional ___________. A ___________is essentially a _________collecting water from ________until there's sufficient _____________ for power generation then forcing the water through ______when released during _________. The world's largest and oldest tidal barrage at La Rance, France began producing power in 1966. Today it still powers 240, 000 homes.

2.5-megawatt wave farm, hydraulic, high pressure oil, 24.5 mln., wave power, half a square mile, captured, hinged joints, semi-submerged, hydraulic ramps, hinges, 454 chain of pipes, generators transmission lines, tethered, 20, 000, 472.

 

____________ is even newer technology. Yet it may hold the most promise of all since wave power can be _______ anywhere on the ocean. In this design a _________________ connected by __________ sits __________ in the ocean. Each motion of the waves is resisted by _________ located in the _________. This action pumps ___________ through __________ modules, which drive electrical ____________. Electrical ___________ also keep the floating power plant ________to the ocean floor.

A Scottish company Ocean Power Delivery has installed the successful ______________off the coast of Portugal. A wave farm occupying less than _________________ of ocean will generate 30 megawatts of power, far enough for __________ British homes. _______ ml2 of ocean could power each of the United Kingdoms _________ households.

4 (b) Answer the following questions on the whole fragment:

1. Has the ocean been tagged as a source of clean energy just recently?

2. Which hydropower source is more promising, river or sea/ocean? Why?

3. What is the principle of operating the tidal barrage?

4. What is ‘tidal stream power'? What's the biggest problem with it?

5. Which turbine, water or air one, is more powerful?

6. Why does wave power hold the most promise?

7. Is there any perspective in building wave farms in Great Britain?

8. How do analysts envisage the future of power generation in the world?

 

5. Now organize a panel discussion: divide into groups and according to the sample above and the following hints, ‘defend' your chosen alternative source of energy. The other groups should mind its disadvantages, costs and future (if any information is available).


<== previous lecture | next lecture ==>
A Conservative Estimate? | Wind farms
lektsiopedia.org - 2013 ćīä. | Page generation: 0.003 s.