Centre of Metallurgic Research Azterlan
Heating and cooling for the new office building of Centre of Metallurgic Research (CIM) Azterlan in Durango, Basque Country is provided by a ground-source heat pump / chiller with a nominal heating capacity of 205 kW, connected to a vertical closed-loop geoexchange system consisting of 23 boreholes. Peak load is covered by a roof-top heat pump with a heating capacity of 240 kW. The installation is working succesfully since March 2006. The Seasonal Performance Factor (SPF) for the period December 2006 to May 2008 was 3,6.
| Country | Spain |
| City | Durango |
| Client name | C.I.M. Azterlan |
| Application area | Industry |
| Building type | Office building |
| Year of construction | 2006 |
| Heat source/sink | Brine/Water |
| Heat pump type | Electric heat pump |
| Year of installation | 2006 |
| Purpose | Heating and cooling |
| Heat source system | Borehole heat exchanger (vertical) |
| Operation mode | Bivalent |
| Refrigerant | R410A |
| Contact name | Iñigo Arrizabalaga |
| Contact E-mail | iarrizabalaga@eve.es |
| Contact website | http://www.eve.es |
Project description
Building, overall energy concept
The new headquarters of CIM Azterlan in Durango, Basque Country is a new building (three storeys plus basement) with a conditioned surface of 3.750 m2 (Photo 1) . Heating and cooling is provided by a 2-pipes distribution system supplying a radiant ceiling and a water/air climatization battery. The heat generation is based upon a GSHP with a nominal heating capacity of 205 kW, connected to a vertical close-loop geoexchange system having a length of 2.780 m, built in 23 boreholes. The GSHP supplies the base load of the building and the main part of the thermal energy demand. The principle sketch of the installation is shown in the figure below.
Design data of the project
- Thermal load of the building:
Heating: 278.551 kWh/year
Cooling: 236.747 kWh/year
- Power consumption of the air-to-water heat pump:
Heating: 112.319 kWh/year
Cooling: 83.069 kWh/year
- Power consumption of GSHP:
Heating: 65.541 kWh/year
Cooling: 53.806 kWh/year
- Geothermal energy output/heat rejection:
Heating: 213.010 kWh/year
Cooling: 290.553 kWh/year
- Final energy reduction GSHP vs. best conventional:
Heating: 46.778 kWh/year
Cooling: 29.263 kWh/year
Heat pump system
Main part of the heat demand is covered by a GSHP/chiller of 205 kW heating capacity (at W7/W45). The heat pump model Dynaciat LG600V was manufactured by Ciatesa. It uses the refrigerant R410a and has two circuits and four scroll compressors. Switching from heating to cooling mode is done by using an external hydraulic circuit based on 2 DN80 four-ways valves (Photo 2).
Operation experiences
The geothermal system is working properly since March 2006. The evaporator outlet temperature is over 5 ºC, using water as heat transfer medium. In cooling operation the condensing temperature is below 35 ºC.
The global performance factor for the period from December 2006 till May 2008 was 3,69 including the energy consumption of the brine pumps and all control devices not included in a conventional system.[Global performance factor = (Thermal energy generation heating+ cooling)/(electrical consumption heating+cooling) along the whole live of the system.]
Main troubles occur in the conventional hydraulic inversion circuit. The two 4-way valves cause up to a 20% of thermal losses, depending on operation conditions and differential pressure between primary and secondary circuits. Several hydraulic troubles are still decreasing the performance of the system that could be improved to more than 4.2. At the moment generation is monitored before and after these valves. The circulation pumps are powered by inverters. There is a full monitoring of thermal energy, generation, electric energy consumption and boreholes production.
Costs, economic efficiency, incentives
- Estimated energy cost savings:
heating: 5.613 Euro/year
cooling: 3.512 Euro/year
- Additional costs against convential air/water heat pump (heating): 176.123,76 Euro
Boreholes (60,6 %)
Civil works & pipes (13.2 %)
Manifold & hydraulic group (9,0 %)
205 kW Chiller ( 10,0 %)
Electric installation, control & monitoring equipment (7,2 %)
- Cost savings (heating):
Not installed 220 kW roof-top heat pump: 40.000 Euro
Subvention as a renewable energy source (RES): 35.200 Euro
Maintenance expenses: 1.500 Euro/year
- Pay-back period (heating): 9,5 years
Regulations, guidelines, benchmarking
Not available.
References
- Infodomus Nº 4. "CIM Azterlan: Piedra, cristal y metal para un volumen horizontal….." Revista Infodomus, nº4, Nov-dic 2006. Portada y páginas 37-46
- Arrizabalaga, I. (2008) "Climatización del CIM Azterlan mediante geointercambio". Libro de ponencias del I Congreso de energía geotérmica en la edificación y la industria. Madrid octubre de 2008
- Arrizabalaga, I. (2008) "Sistemas geotérmicos en circuito cerrado C.I.M. AZTERLAN, DURANGO (205 kW)". Seminario proyecto ASTECH. Bilbao noviembre 2008
| Design value | Measured data | |
|---|---|---|
| Year1 | 2005 | 2006 |
| Heating capacity (kW)2 | 205 | >205 |
| Cooling capacity (kW)3 | 182 | >182 |
| COP (Heating, appliance) | 4,0 | >4,0 |
| EER (Cooling, appliance)4 | >13,65 | up to 20 |
| SPF (Heating)5 | 3,60 | |
| SEER (Cooling)6 | 3,82 | |
| Annual heat delivery (kWh/year)7 | 278.551 | 153.200 |
| Annual cooling delivery (kWh/year)8 | 236.747 | 120.750 |
| PER (Heating /Cooling)9,10 | 1,44/1,53 | |
| Annual CO2 emissions (kg CO2/year) | 25.216 |
1 Monitoring results covering the period from December 2006 till May 2008.
2 Up to 240 kW
3 Up to 240 kW
4 In passive cooling (geocooling) mode.
5 Including the energy consumption of the brine pumps and all control devices not included in a conventional system. Chiller production up-ward 4-way valves leakage: 4.14
6 Including the energy consumption of the brine pumps and all control devices not included in a conventional system. Chiller production up-ward 4-way valves leakages: 4.26
7 2006/2007/2008 were warm winter years
8 2006/2007/2008 were cool summer years
9 Primary Energy Ratio: Useful heating (and cooling) energy delivered / primary energy input (kWhUE / kWhPE)
10 1,66/1,70 Chiller production
| Institution/Company | C.I.M. Azterlan |
| Responsibility/Function | Owner, explotation management |
| Street/PoBox | Pol: Montorreta |
| ZIP | 48200 |
| City | Durango |
| Country | Spain |
| Contact Person | J.M. Murua |
| Phone/Fax | +34 94 6215470 / +34 94 6215471 |
| jmurua@azterlan.es | |
| Website (URL) | http://www.azterlan.es |
| Institution/Company | EVE Basque Board of Energy |
| Responsibility/Function | Design, construction and funding |
| Street/PoBox | Alda. Urquijo, 36-1º |
| ZIP | 48011 |
| City | Bilbao |
| Country | Spain |
| Contact Person | Iñigo Arrizabalaga |
| Phone/Fax | +34 9440 35600 / +34 9440 35699 |
| iarrizabalaga@eve.es | |
| Website (URL) | http://www.eve.es |
