GROUND-MED PROJECTCOIMBRA DEMO-SITE

André Quintino Duarte

Coimbra, 23 February 2012

Demonstration Building

Total area: 3250m2

Four floors

Two public services installed

Offices, laboratories, conference room

Capacity for 250 permanent workers + 72 temporary people in a conference room

Located close to a river

“Fábrica dos Mirandas”

Demonstration Building

Demonstration Building

• The heated /cooled spaces are located in level 3 of the building (last floor).

• 22 rooms (offices)• Approximately space conditioned area 600 m2

Demonstration Building

Simplified schematics of the hydraulic installation

75 mm Diameter PPR Pipes in the main sections

Borehole Heat Exchanger

DOUBLE U TUBEBorehole diameter (d) 160 mm

Pipe internal diameter (D2) 32 mmPipe external diameter (D1) 35 mm

Shank spacing (s) 56 mm

• Seven vertical boreholes• 125 m deep • 5x5 m rectangular grid• grout material is graded sand (pea size - 3-8 mm )

Geological Profile

Alluvium

Limestone / Sand / Silt

Clay Loam

Earthworks

High Groundwater flowFreatic Groundwater level – 5 metres

Location of the Boreholes

Heat Pump• Reversibility is done on the

water side in order to always be in counter current on the heat exchangers.

• This is achieved by 3-way motorized valves

CondEvap

Piping System

Heat Pump Test Results

Conditions

Cooling modeEvaporator Condenser

Cooling capacity

EEREuroventClass AInlet Outlet Inlet Outlet

EUROVENT 12°C 7°C 30°C 35°C 56 kW 5.05 >= 5.05

Coimbra demo site

15°C 10°C 25°C 30°C 63.5 kW 6.19 n.a.

Conditions

Heating modeEvaporator Condenser

Heating capacity

COPEuroventClass AInlet Outlet Inlet Outlet

EUROVENT 10°C * 40°C 45°C 61 kW 4.58 >= 4.45

Coimbra demo site

15°C ** 35°C 40°C 70.4 kW 5.65 n.a.

The performance of the heat pump prototype was tested at the CIAT Culoz research center.

Heating Capacity – 70.4 kWCooling Capacity – 63.5 kW

Circulation Pumps

High efficiency permanent magnet motor pump supplied by Grundfos, with variable speed control.

FanCoil Units• The Fan Coil units were supplied by CIAT. They are

COADIS 2 fancoil units models 235/22 and 235/33. A total of 33 units were installed – 23 units of model 235/22 and 10 units of model 235/33.

• These fancoil units are equipped with high efficiency impellers and high efficiency permanent magnet motors.

FanCoil Units

FanCoil Units

FanCoil Units• Each fan coil can be individually regulated by means of a

thermostat. Comfort temperature can be selected by the user by means of a wall mounted control and fan speed is controlled automatically by means of a 0-10V control signal.

• The fancoils had to be retrofited with an electronic fan speed limiter, because of the noise generated was unacceptable by the users.

Location of the fancoil units

Thermal Storage• The thermal storage tank is to be located in a room

adjacent to the machinery room. It is planned to have a volume of 3.5m3 (40% water + 60% PCM).

• Research is being conducted with the support of the Fluids Thermal Transfer Group of the Department of Mechanical Engineering on the best design of the tank to ensure optimal heat transfer and to ensure that the storage maximum capacity of the PCM modules is used.

• It was found that the most suitable material would be the S46 salt hydrate from PCM products Ltd (UK)

Preliminary test results

Preliminary test results

Preliminary test results

Preliminary test results

COP = 6,03

Thank you