GEOTHERMAL DIRECT HEAT UTILIZATION. DISTRICT HEATING.
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Transcript of GEOTHERMAL DIRECT HEAT UTILIZATION. DISTRICT HEATING.
GROUND SOURCE HEAT PUMP
(a) Categories of Capacity % for 2005 and (b) (b) energy use in %, 2005
(Lund, Freeston and Boyd, 2005).
DISTRICT HEATING
Distribution of hydrothermal water from one or more wells to several houses, buildings and blocks
• It is the largest sector of geothermal energy direct use in the world.
• It involves the distribution of heat (hot water or steam) from a central location, through a network of pipes to individual houses or blocks of buildings.
• Geothermal Heating Systems are in operation in at least 12 countries.
DISTRICT HEATING
Heat Pump Technology
• The Earth as a heat source and sink
• Heating in winter and cooling in summer
• In the USA and Europe
GROUND SOURCE HEAT PUMP
GHPs use the stable temperature of the ground;
• as a heat source to warm buildings in winter
• as a heat sink to cool buildings in summer
• also for water heating by desuperheaters
GROUND SOURCE HEAT PUMP
The system includes three principal components:
• Geothermal earth connection subsystem • Geothermal heat pump subsystem • Geothermal heat distribution subsystem
GROUND SOURCE HEAT PUMP
Earth Connection Subsystem
• buried in the ground near the building • either vertical or horizontal• circulates a fluid (water, or a mixture of water and antifreeze)
GROUND SOURCE HEAT PUMP
A heat pump is a device which uses heat on a low temperature level, and transfer the heat to a higher, useful
temperature level using an external driving force (mechanical energy or high-temperature heat)
GROUND SOURCE HEAT PUMP
A heat pump is a device which uses heat on a low temperature level, and transfer the heat to a higher, useful
temperature level using an external driving force (mechanical energy or high-temperature heat)
Heat flows naturally from a higher to a lower temperature. Heat pumps, however, are able to force the heat flow in the
other direction, using a relatively small amount of high quality drive energy (electricity, fuel, or high-temperature waste
heat). Thus heat pumps can transfer heat from natural heat sources in the surroundings, such as the air, ground or water,
or from man-made heat sources such as industrial or domestic waste, to a building or an industrial application.
GROUND SOURCE HEAT PUMP
GROUND SOURCE HEAT PUMP
In order to transport heat from a heat source to a heat sink, external energy is needed to drive the heat pump.
Because heat pumps consume less primary energy than conventional heating systems, they are an
important technology for reducing gas emissions that harm the environment, such as carbon dioxide (CO2),
sulphur dioxide (SO2) and nitrogen oxides (NOx).
GROUND SOURCE HEAT PUMP
Almost all heat pumps currently in operation are either based
on a vapor compression, or on an absorption cycle.