Ziel
To manufacture and test 18 prototypes of a new heat pump with a thermal engine offering improved performances and lower production cost.
On the basis of calculations and laboratory testing, the energy savings in comparison with traditional boilers, was projected at 50%. On this criterion, it was decided to test 18 prototype heat pumps with a view to developing a model for industrial production throughout Europe. However, the mid 1985 drop in fuel prices meant that commercial development was less economically feasible, and the project was finally abandoned at the end of 1985.
The prototypes were tested as follow;
- 10 in private houses;
- 4 in the Rueil workshop, in a climatic chamber;
- 1 by Gaz de France, for official approval;
- 3 in industrial premises of firms interested in the project.
Results are only available for the first two of these.
Laboratory/workshop testing at Rueil was used to solve problems and refine operation before installation.
During testing, problems arose with the diesel version, caused by dirt on the heat exchangers: a heat exchanger was specifically designed and operated sucessfully, maintaining speed at >15m/s.
Of the breakdowns which occured in the first year, these coudl be grouped into the following:
- breakdown due to defective installation or manufacture, or non-compliance with consultant's instructions;
- fatigue breaks due to excessive loading;
- damaged circuit boards, caused by condensation: this was solved by improving waterproofing between compartments.
Of the 11 breakdowns which did occur, 8 were attributed to faulty installation/manufacture, 2 to prototype problems and one as the result of mechanical failure.
However, the behaviour of the equipment was felt to be generally satisfactory, although these faults illustrate the importance of good quality control at all levels of manufacture and installation.
Total heat pump operation was recorded at 34,733 hours, and engine operation at 10,821 hours, and the performance of pumps tested in-situ was better than laboratory tested pumps:
- weighted COP figure over heating season 'typical Paris 'climate: 1.55
-thermal power at - 10 deg. C external temperature:
at 3000 rpm 18kW
at 3400 rpm 20 kW
- regulation of domestic heating to + 0.2 deg. C
Technically, the thermal power figure obtained should provide heating and hot water in a typical 'Paris climate' in a surface area of 350-400 m3, with a G value of 1.6 to meet an annual heat requirement of 25,000 kW/h.
The energy saving is 40-60%, when comparing PACTOL with either a modern boiler or an older one.
The project consists of component purchase, prototype heat pump assembly, installation of these at private homes around Paris and testing them in long term operation and, finally, analysing the results of the test campaign.
The "Pactol" heat pump includes a miniaturised thermal engine and can fully replace a 20 Kw boiler without the need for a back-up system. It contains, among others, the following innovative features: - the thermal engine and the exchanger in contact with the exhaust gases operate in the same container where a part of the heating water circulates. The exhaust gases are thus cooled down to 60-100 deg C.
- the exhaust gases then flow to freon reflux-absorbing cylinder, itself used as an exchanger, which improves the performance of the system.
- a hot water tank to store excess heat during warmer weather periods thereby helping to smooth out the operating cycles.
- a continuous de-icing and de-scaling of the evaporator by means of a temperature variation recordingsystem.
The cost of a "Pactol" heat pump is FF 34,000 installed, compared to FF 16,000 for a modern boiler The system also costs FF 600/year in additional maintenance, but affords a 4-year payback under the climatic conditions of the Paris area, compared to a fuel based heating system generating 80 deg C water in a -10 deg C outside temperature.
No mention of patent coverage is made in the project.
Thema/Themen
Aufforderung zur Vorschlagseinreichung
Data not availableFinanzierungsplan
DEM - Demonstration contractsKoordinator
75739 PARIS
Frankreich