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2. Reasons for the use of solar energy for heating and cooling . Reduces operational costs of facilities Reduces dependency on fossil energy supply and/or electricityContributes to a healthy environment by cooling without the use of toxic gasesUse of renewable energy contributes to the reduction of CO2 emissions.
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1: 1 Cooling and Heating (large) facilities with the supporting power of the …the absorption cooling process converts water heated to 80 degrees by fossil fuels or the power of the sun to cold water of about 8 degrees…
2: 2 Reasons for the use of solar energy for heating and cooling
Reduces operational costs of facilities
Reduces dependency on fossil energy supply and/or electricity
Contributes to a healthy environment by cooling without the use of toxic gases
Use of renewable energy contributes to the reduction of CO2 emissions
3: 3 Saving money through Solar energy utilisation Amortisation after only 5 years possible**
Conventional heating / cooling systems do not have an amortisation potential
Low operational costs facilitate higher profits
4: 4 Solar applications in Europe On the increase with;
Greece being the largest user of installed solar an collectors with annual sun radiation* of 1500 kWh/m2
GR is followed closely by Germany & Austria with an annual radiation of only
950 – 1200 kWh/m2
Mediterranean countries with values of >1500 kWh/m2 utilize solar energy least
5: 5
6: 6 The reduction of CO2 emissions was agreed at Kyoto** & adopted by the EU
50% of the green house effect is
caused by burning of fossil fuels (CO2)
and 22% by CFCs & HFC gases
used in conventional cooling
A reduction can only be achieved if;
renewable energy systems are used
cooling systems are used which do
not use toxic gases (absorption cooling)
Solar utilisation reduces CO2 emissions….
7: 7 to support political programmes in reducing CO2 emissions… The EU target until 2012…
8: 8 Solar energy is available throughout the year to; Heat during the cold months with temp.< 60oC
Cool, using an absorption thermo chemical process during hot months with temp. > 80oC
9: 9 Components in the utilisation of solar energy facilitating cooling Solar collectors achieve yields up to 0,6 kW/m2
Modern heat exchangers have low heat losses
Use of large buffer storage tanks to retain collected energy
Separating sanitary water from buffer water
Absorption cooling requiring heat > 80oC which is achievable through solar energy in summer
Tele-monitoring of the controls (also from abroad) to optimise efficiency of plant
10: 10 The absorption cooling cycle …is similar to a vapour compression
cycle in that it relies on 3 basic principals;
When liquid is heated it vaporizes (boils) and when gas is cooled it condenses
Lowering the pressure of a liquid reduces its boiling point
Heat flows from warmer to cooler mediums
11: 11 absorption cooling–continued Instead of mechanically compressing a gas, the absorption cooling relies on a thermo-chemical compressor
Two different fluids are used that dissolve easily in one another;
water under a vacuum as refrigerant
ammonia or LiBr* as an absorbent
The refrigerant (water) can change from liquid to vapour state easily and is circulated through the system driven by the heat of the solar plant >80 degrees
12: 12 The Environmental Benefits The ammonia used in the closed cooling system is safe, odourless and non-toxic
Ammonia carries no risk to the ozone layer
The hot water heated by the sun used as the primary energy source carries no risk to the environment
Should a support* energizer be required, waste product combustion can be used as well as any conventional energy source such as gas, oil or electricity
13: 13 Solar Cooling of EAR Tower
14: 14 Cost and Efficiency for Solar Heating and Cooling Plants depend on; Location of building in respect to the sun
Quality of building in respect to thermal insulation and glazing standards used
Usable floor area of the building
Buffer size to store heated water during periods of reduced solar yield
Heating / cooling requirements of the users
Type of supporting energizer
15: 15 Indicative cost for a complete solar heating/cooling plant… Cost per m2 usable area is ~200 €*, for;
Design, commissioning of plant (consultant services)
Solar plant for heating/cooling made up of;
the required solar collectors (~15% of usable floor area)
heat exchanger and pumps
buffer reservoir with separate boiler for sanitary water
absorption cooling machine with cooling tower
fan coil units to dissipate the energy
Waste combustion, gas or oil fired support system
Control components and tele-monitoring
16: 16 Consultancy Services and Tools….
17: 17 …noting that; the herein described system is hydraulic as it is more efficient to air based systems to transport the collected solar energy*
all air ventilation needs are to be dealt with separately which will increase the cost of the plant by up to 50 €/m2 floor area
the energy required to heat or cool the circulated air can be supplied by the described system at no extra cost
The square meter price for solar collectors do not exceed 200 €/m2 with yield of 0,6 kW/m2
18: 18 Situation in Kosovo… KEK* produces approx. 3 GW of electricity by coal per annum (losses not considered)
It is assumed that about 2,2 M people live Kosovo in about 280 T households
That puts the per head consumption at 1,364 kW/per annum against Portugal** with 4TkW/a
Consumption per household 10,714 kW/annum
Noting that about 30% of the population live in urban centres…
It is assumed that people living in towns will consume double to the pop living in villages
19: 19 Household consumption… of people living in towns could be as high as 25,000 kWh* per annum per household
This amounts to an energy need of up to 250 kW/h/m2 usable floor area assuming a 100 m2 dwelling, against current EU needs of 100 kW/h/m2 (in similar climatic conditions)
This energy need can be reduces by 20%, if;
the facility receives thermal insulation (external)
the facility receives air tight windows / doors
the windows / doors receive thermal glazing
the roof / basement are sufficiently insulated
20: 20 What actions should be set to reduce the energy need? Energy consumption of a medium sized house should be reduced from 250 kW/m2 per year to at least 100 kW / m2 / year
To reduce demand by 60% of current e-usage a combination of activities are required
21: 21 Energy saving in residential houses Further savings can only be achieved if alternative energy systems are used for;
Heating or cooling a facility (15%)
Heating up sanitary water (15%)
Cooking (10%)
For the hydraulic systems solar plants are recommended whilst for cooking, gas is the only real feasible alternative
22: 22 Potential Saving per household By an annual electrical consumption of 25 mWh,
or 2,083 kWh* per month, installing alternative
heating systems for;
hot water, can save 6,5 mWh per annum
central heating, save 6,0 mWh per annum
cooking with gas instead of electricity
the total electrical power thereby saved per annum
will amount to ~15 mWh, saving 750 €** from the
annual electricity bill
23: 23 Producing components that can be used to utilize solar power, e.g.;
Solar collectors
Boilers (used as buffer storage tanks)
Making and installing solar heaters
Making and installing central heating systems for residential and public buildings
Photovoltaic technology and their applications
Thermal insulation;
Material production, also organic
Providing thermal façades to facilities Market Potentials for Kosovo?
24: 24 Companies involved in the Solar Plant at the EAR Tower*