IEA Solar Heating and Cooling Programm - NachhaltigWirtschaften.at

IEA SHC Task 38 Solar Air Conditioning and Refrigeration
Subtask A Report, Date:…
Jan Feb Mar Apr May Jun Jul
2010 2010 2010 2010 2010 2010 2010
0,77 0,90 2,05 3,68 1,22 1,45 1,43
Again the results are strongly related to the studied month. The Primary energy ratio can
reach 3,68 in April 2010. But they also can be lower than 1.
An average based on the year from July 2009 to June 2010 was calculated, and it leads to a
PER equals to 1,10. Once again, even if this value is higher than 1, it is not very high.
In addition to the large amount of electricity consumed by the different electrical devices (as
explained in the previous paragraph 5.3), the backup is an electrical one. And the amount of
primary energy to create one kWh of electrical energy is very high, as a consequence, the
PER is lower than in the case where another type of backup is used.
5.5 Fractional solar heating and cooling savings
The global evaluation of the whole system was performed by using the fractional solar
heating and cooling savings fsav,SHC performance criteria. It calculates the ratio of the
fraction of energy savings of the solar system to energy consumption of a conventional
system that fulfils the same demand for heating, cooling and domestic hot water. The
calculation was achieved by considering the conventional system as using fossil electricity.
This value is calculated monthly for the working period, and the results are shown in Table 6.
Table 6: Mothly fractional solar heating and cooling savings for the Chambery installation
May Jun Jul Aug Sep Oct Nov Dec
2009 2009 2009 2009 2009 2009 2009 2009
-63,74% -19,18% 2,14% 13,15% 4,73% -195,8% -12,99%
Jan Feb Mar Apr May Jun Jul
2010 2010 2010 2010 2010 2010 2010
-5,88% 9,12% 60,08% 77,70% 10,11% 22,83% 21,51%
The results are closely related to the studied month. The fractional solar heating and cooling
savings can be high up to 77,7% (for April 2010), but they can also be negative.
An average value based on the year from July 2009 to June 2010 was calculated, and it
leads to a fractional solar heating and cooling savings equals to 14,80%. Even if this value is
positive, it is not very high, and the explanations are the same than in the previous
paragraph (5.4): because of the “experimental state” of the system, a lot of devices
consuming electricity are part of the installation design, and in addition an electrical boiler is
used in the hot tank which is disadvantageous when the calculations are based on primary
energy.