Geothermal Energy Overview and Resources

Geothermal Energy Overview

• Geothermal energy is derived from Earth's internal heat.
• This heat is a renewable, reliable, and efficient energy source.
• Current prices range from 5-8 cents/kWh.
• The temperature of the rock increases approximately 3°C for every 100 meters below ground.
• Hot water reservoirs, close to Earth's hot rock, can reach temperatures exceeding 150°C.
• Hot springs and spas are popular globally due to low sulfur content.
• Other applications include agricultural production, aquaculture, industrial processes, and heating.

Geothermal Resources and Applications

• Geothermal resources are categorized based on temperature ranges:
  • High temperature (>220°C) suitable for power generation using various methods
  • Intermediate temperature (100-220°C) suitable for direct use
  • Low temperature (50-150°C) ideal for direct use (e.g., heat pumps)
• Direct-use applications include processes like drying, refrigeration, and various heavy industrial processes.
• Power generation methods like flash steam, binary cycle, and combined systems are utilized.
• Technology choices depend on the reservoir temperature and intended use

Geothermal Maps of Canada

• A map depicting the estimated geothermal resources in Canada is shown.
• This map highlights regions with potential for various geothermal applications.
• Highlighted areas indicate high geothermal heat flow.
• The intensity of these regions on the map represents varying resource estimates.
• There are areas of Western Canada & parts of Eastern Canada with estimated resources like Mega Creek (300MW), Pebble Creek (200MW), & Test Hole (3MW).

Geothermal Power Generation Methods

• Five common methods: direct steam, flash steam, binary cycle, flash binary, combined geothermal
• These methods differ in their approach to harnessing geothermal energy and extracting useful output (i.e. steam) from geothermal sources.

Geothermal Energy Use Globally

• United States is the leading geothermal electricity producer, with 3,567 MW currently in production.
• Further 1,270 MW of projects under development.
• Top countries (2023) based on installed capacity (MWe) include U.S., Indonesia, Philippines, & Turkey.
• A considerable global geothermal energy resource exists, with countries utilizing various methods.
• Canada's geothermal energy use is comparatively limited despite being well-positioned to utilize the resources available.

Geothermal/Ground Source Heat Pumps

• Geothermal/ground source pumps exploit constant ground temperatures for heating and cooling.
• This technology taps into the constant temperature of the Earth's crust for homes.
• Constant earth temperatures allow heating/cooling systems to operate effectively year-round.

Power Plant Types

• Dry steam power plants directly utilize high-pressure steam from geothermal sources for power generation.
• Flash steam plants utilize this energy for power generation.
• Binary cycle power plants employ a secondary working fluid (i.e., an organic fluid) to convert heat into power.
• The selection of a particular power plant will depend on the thermal characteristics of the geothermal fluid.

Double-Flash Steam Power Plant

• Improves on single-flash plants by utilizing the still hot water from the initial flash stage to generate more steam within a secondary flash chamber.
• This extra steam conversion increases power output.

Binary Power Plant Analysis

• Binary cycle power plants use a secondary working fluid.
• This fluid has a lower boiling point than water.
• The heat contained in the hot geothermal fluid raises the temperature of this secondary fluid, transforming it into steam and generating electricity.

Flash-Binary Power Plant

• Flash-binary power plants combine the flash steam and binary cycle methods.
• They are suitable for medium to high-temperature geothermal resources.

Geothermal Combined Cycle Plant

• Geothermal combined cycles employ a multiple method strategy that utilizes high-grade steam for larger scale power generation.
• This method utilizes waste energy outputs with additional heating/cooling capacity.

Closing Remarks

• Geothermal energy is a renewable and environmentally friendly source.
• Geothermal power systems are cost-effective for electricity
• Applications span electricity, geothermal heating, cooling, and power generation.
• Integration with other energy systems for hydrogen production is possible, as ground source heat pumps are widely deployed.

This quiz explores the fundamentals of geothermal energy, including its sources, applications, and pricing. Learn about the different temperature classifications of geothermal resources and their various uses across industries. Test your knowledge on this renewable energy topic.