Tidal energy

Unit 7

PART 2

Speak on the seven ages of geothermal development.

Determine the main idea of each paragraph.

• Answer the questions using the information from the text below. Think of the title to the text.

1. What is an example of a geothermal direct use application?

2. What technology allows high efficiency?

3. When are there no C0₂ emissions?

4. How many units have been established in Louisiana?

5. Where is currently the main activity?

6. What countries are the members of the Geothermal Heat Pump Consortium?

7. What are the benefits of geothermal technology?

Geothermal heat pumps, or ground-source heat pumps, for heating and cooling buildings are a rapidly growing example of a geothermal direct use application. The technology has developed almost without publicity in recent years to become a significant new factor in the supply equation. This is an electrically-based technology that allows high ef­ficiency, reversible, water-source heat pumps to be installed in build­ings in most geographical and geological locations (worldwide). The combination of increasing levels of electrical generation efficien­cy, with the impressive energy amplification' of geothermal heat pumps means that space heating can be delivered with effective efficiencies that exceed² 100%. The "additional" energy is supplied from the ground. In addition these systems also offer highly efficient cool­ing. The types of buildings that are using ground-source heating and cooling in this manner range from small utility or public housing, through to very large (MW-sized) institutional or commercial build-mgs. This technology can offer up to 40% reductions in C0₂ emissions against competing technologies. If all of the electricity is supplied from non-fossil sources, there are no C0₂ emissions associated with heating and cooling a building.

Recently, several large-scale arrays³ have been installed to feed larg-^er systems where suitable supplies of deep geothermal water are not ^available. In the largest development to date, 4000 units - each with its own borehole - have been established on a US Army base in Loui-^{Slana to} provide heating and cooling.

Section I. Power Engineerin g _Unit 5. Geothermal Energy

The concept was developed independently in the US and Europl and, although Sweden and Switzerland have installed many thousand) of units to provide winter heating in houses, the pace of installation iJ the USA and Canada during the last fifteen years has overtakerl the European rate. There are now believed to be well over a quarter J a million installations in place in North America.

While the main activity is currently in the USA, there are a growinl number of installations in Canada, Sweden, Switzerland, Austria anq Germany. Smaller numbers are being installed in other European coun tries, and in Australia. The Geothermal Heat Pump Consortium cub rently has over 750 institutional, corporate and commercial members! and 40 international members from countries including AustraliJ Canada, China, Croatia, Finland, Germany, India, Japarl the Netherlands, Poland, Russia, Sweden, Turkey, and the UK. I

Ground-source heat pumps are perhaps the first indication oi the seventh age of geothermal technology, breaking the final barrier ol geographical availability.

To sum up: geothermal technology offers many benefits — clean! indigenous, firm energy — but suffers from economic uncertainties and geographical limitations. These problems are being actively addressed and future prospects seem bright.

1 — усиление; 2 — превышают; 3 - структуры; 4 - обогнал

IT IS INTERESTING TO KNOW

• Read and retell the text.

Multiple Use of Low Temperature Geothermal Water in Erding

Reclamation and reuse of a former gas exploration borehole wii provide geothermal water for a distinct heating system and drinking water for the town of Erding, Germany. As well as providing these di-j rect benefits to the town, implementation' of the scheme will result iru a reduction in the consumption of fossil fuels to generate energy, with! a subsequent positive impact on the environment, and reduced pres-| sure on existing supplies of drinking water.

About 552,000 cubic metres of geothermal water will be extracted from the borehole each year and cooled, using a heat exchanger an^

heat pump, from a temperature of about 65 °C to between 17 ° and 23 °C. The absorption-type heat pump is designed for two-step opera­tion, to give a high heating efficiency. The new district heating net­work, with a capacity of 17MW, will supply water, at a temperature of about 40 °C, to residential areas², hospitals and schools. Compared to the conventional system of energy supply currently in use in Erding, the energy produced by this new scheme will replace the equivalent of 29,000 MWh per year of energy generated from fossil fuels (about 51 % of energy use). Once the district heating scheme is established, the geothermal water extracted will be purified³ and treated (by de­gassing, filtration and ozonation) for use as drinking water, which will be blended with the existing water supply.

1 — осуществление; 2 — жилые районы; 3 — очищена

• Open a round table discussion on thermal power in our country and abroad using the following questions:

What do you think of...? What is your opinion of...? Do you think that...? Do you agree that...? Is it really so?

Unit 7. Tidal Energy

Дата добавления: 2015-05-08