Blog – Full Width | AEA-Albania Energy Association

May 8, 2011

by AEA

EUREC Agency

European Renewable Energy Research Centres Agency

The European Renewable Energy Research Centres Agency was established as a European Economic Interest Grouping in 1991 to strengthen and rationalise the European research, demonstration and development efforts in all renewable energy technologies. As an independent member-based association, it incorporates 49 prominent research groups from all over Europe.

EUREC members’ research fields include all renewable energy technologies (wind, biomass, small hydro, marine, geothermal, photovoltaics, solar thermal power and solar buildings). Our members also conduct research into supporting technologies such as energy efficiency, storage, distribution and integration. Moreover, they study the social and economic aspects relevant to renewable energy. (http://www.eurec.be)

May 6, 2011

by AEA

Onsite renewables

Renewable heat and power provision for buildings, developments, estates and communities

Use of onsite renewable power generation can lead to significantly lower electricity bills and fewer greenhouse gas emissions.

A wide variety of renewables can be installed onsite, producing energy directly for the building or community rather than having to transport it from power stations elsewhere.

Wind generators

In suitable locations, integrated wind energy can be an effective source of renewable power generation. Wind speed is greater at height, so this particularly suits tall buildings.

Solar power

Either photovoltaic panels that generate direct current electrical power in sunlight, or solar water heating systems can be used.

Biomass boilers

Swapping conventional domestic boilers for biomass boilers, which burn wood chips and pellets makes heating a building a carbon neutral process.

Borehole cooling

As ground temperature is well below air temperature in summer, boreholes can be used to extract cool ground water to supplement building cooling systems.

May 6, 2011

by AEA

Heat networks

A heat network distributes heat to several users, just as an electricity grid distributes power.

The heat energy produced and recycled by Combined Heat & Power plants during electricity generation can be sold and distributed to local homes and businesses via a heat network. Several thousand homes can be connected to a heat network.

Heat networks can also be constructed to distribute heat from Geothermal energy.

The networks have a long lifetime and are flexible to almost any source of available heat.

Recycling heat in this way has an important role to play in the reduction of carbon dioxide emissions. It is estimated that for every 100,000 MWh of energy supplied via heat networks, 31,000 tons of carbon dioxide emissions are avoided.

May 6, 2011

by AEA

Combined Heat & Power

Forms of power generation using combustion can generally be made more efficient if the surplus heat is captured and used too. This is called Combined Heat and Power (CHP).

In conventional power generation the large amount of heat produced as a by-product is lost. Combined Heat and Power technology puts this heat to use, recycling it for use in community heating or for industrial purposes. This makes CHP a much more fuel efficient method of power generation, increasing overall efficiency of fuel use to more than 75% compared with the 50% achieved by conventional power generation.

A variety of fuels can be used to power a CHP generator, as well as fossil fuels these include renewable sources such as Biomass, Geothermal and Solar Energy.

A CHP plant consists of one or more prime movers, such as a reciprocating engine, gas turbine or steam turbine which drives an electrical generator. The steam or hot water generated is then used rather than wasted.

CHP plants are generally smaller than electricity plants and are usually attached to a site that consumes all or most of the heat and power it produces.

High capital and maintenance costs mean CHP is more often used by the industrial, commercial or public sector rather than individual domestic users. It is popular with those requiring large amounts of heat, such as hospitals and leisure centers. As the plants generally supply electricity locally they also avoid transmission and distribution losses associated with conventional electricity supplies.

The increase in fuel efficiency means Combined Heat and Power is playing an increasingly important role in reducing carbon dioxide emissions, achieving reductions of as much as 50%.

Converting to Combined Heat and Power also lowers emissions of sulphur dioxide and nitrogen oxides, reducing acid rain.

May 6, 2011

by AEA

Solar heating

Active solar heating systems convert solar radiation into heat which can be used directly.

In the Albania uses are primarily domestic water heating and other low temperature heating applications. In hotter climates a wider range of applications is possible, including electricity generation.

There are two types of solar water heating systems, Direct and Indirect. With Direct systems the water flowing in the collector tubes is the same as the water circulating in the tank and comes out of the taps, With Indirect systems the heat transfer fluid circulating around the system does not come into direct contact with the water coming in the tank or coming out of the taps.

Domestic water heating schemes consist of solar collectors, pump, control unit, connecting pipes, and backup heat source such as gas or electric immersion heater. With Direct hot water system, the existing hot water tank can be retained. However for Indirect systems, if the existing hot water tank is to be retained a pre-heat tank will be required. Alternatively the existing single coil hot water tank can be replaced with a twin coil tank removing the need for a preheat tank.

The overall area of the panels is typically 3-4 square meters.

Renewable electricity generating technologies such as photovoltaic’s and wind turbines can be used to offset the small amount of carbon emissions arising from the electric pump circulating water around the solar hot water system.

May 6, 2011

by AEA

Heat pumps

These are devices that can extract and amplify heat obtained from a source of thermal energy.

There are several types of heat pump. All use the same basic principle of extracting heat from a source and concentrating it to obtain a higher temperature, usually then applied to water for domestic heating and hot water.The device which does this can be thought of as a refrigerator operating in reverse. It is powered by electricity, but the amount of heat energy delivered is several times more than the electrical energy consumed. The ratio of the output to the input energy is called the Coefficient of Performance (COP).As heat pumps transfer rather than produce heat they are more efficient than traditional heating systems.

Ground source heat pumps

Obtain their heat energy from the ground. The temperature of the soil even just a meter down is very stable throughout the year in the UK.The ground heat is captured using water passed through pipes buried in the ground. These can be either coils buried in the topsoil, or one or more boreholes sunk deeper into the subsoil.

Air source heat pumps

Obtain their heat from the ambient air, using a fan unit located outside the building. The pump converts heat from the air into more useful energy through a heat exchanger.Air source heat pumps can save more than 2 tons of carbon a year, emitting 50% less than gas boilers and 70% less than electric systems.As well as being used to heat in winter their cycle can be reversed to cool in the summer, when the unit takes heat out of the indoor air and releases it outside.

Water source heat pumps

These are rather rarer, using heat from a pond, lake, river stream or other body of water, to provide heating for nearby homes.The water is drawn in to the pump’s heat exchanger, where the heat is extracted and the water is returned to the source.