State of the Art of HVAC Technology inEurope and America
Bjarne W. Olesen
International Centre for Indoor Environment
and Energy
Department of Civil Engineering
Technical University of Denmark

Heating and Cooling of Buildings• Heating, cooling and ventilation systems play a significant
role in the energy use (42%) and for the indoor
environment quality in a building• The main purpose of these systems is to provide a
comfortable, healthy and productive indoor environment
for the occupants• These goals should however be achieved with the lowest
possible energy consumption.

COMFORT-PRODUCTIVITY
Building costsPeople100
Maintenance 10
Financing
10Energy1Energy Demand-Energy EfficiencyEnergy Sources• As the resources of fossil fuels are limited and the use of nuclear
power is associated with several safety issues there is a worldwide
need for reducing the energy demand of buildings.
• Reducing the energy demand is much more efficient andsustainable than increasing energy sources• When constructing new buildings and renovation old buildings
the first priority is to decrease the energy demand

POSSIBLE ACTIONS• Decrease energy demands (building design)• Increase energy efficiency (HVAC systems)• Increase use of renewable energy sources(wind, solar, geothermal, biomass)• New energy sources (fuel cell)

The 20-20-20 EU policy by 2020
New policy for 2030 proposed
100% (1990)-20 -40%-20 -40%

2027%
8,5%

Greenhousegas levels

EnergyUse

Renewables inenergy mix

Required reductions inenergy use in European
countries
2020 in relation to 2005

National overall targets for the share of energy from renewablesources in gross final consumption of energy in 20202005-2020
Belgium
2,2Bulgaria
9,4
Czech Republic 6,1Denmark
17,0Germany
5,8
Estonia
18,0Ireland
3,1Greece
6,9Spain
8,7France
10,3
Italy
5,2Cyprus
2,9Latvia
32,6Lithuania
15,0
Luxembourg 0,913 %
16 %
13 %
30 %
18 %
25 %
16 %
18 %
20 %
23 %
17 %
13 %
40 %
23 %
11 %

2005-2020
•
•
•
•
•
•
•
•
•
•
•
•

Hungary
4,3 % 13 %Malta
0,0 % 10 %Netherlands 2,4 % 14 %Austria
23,3 % 34 %Poland7,2 % 15 %Portugal
20,5 % 31 %Romania
17,8 % 24 %Slovenia
16,0 % 25 %Slovak Republic6,7 %14 %Finland
28,5 % 38 %Sweden39,8 % 49 %United Kingdom 1,3 % 15 %Part of renewable energy sources(wind and bio-fuel) in Denmark(no nuclear)

The effect ofbuildingregulations

ZEB Concept
Over the course of a year, if
the (on-site or source)
renewable energy produced ≥the energy used within theboundary, it is considered aZEB?

17

Energy Efficient Technologies•

Indoor air quality– Reduce loads (pollution sources)– Heat recovery– Increase system efficiency– Natural ventilation-Hybrid ventilation– Air distribution (contaminant removal) effectiveness• Personal ventilation– Air cleaning•

Thermal comfort– Reduce loads (building shell, solar screen, internal loads)– Increase system efficiency– Low Temperatur Heating- and High Temperature Cooling Systems– Use of building mass to reduce peaks (Thermo-Active-BuildingSystems (TABS))– Drifting indoor temperatures

Low Temperature Heating –High Temperature Cooling• Low Temperature Heating (LTH) and High Temperature
Cooling (HTC) systems are an important requirement forincreasing the energy efficiency of HVAC (heating,ventilation and air-conditioning) systems and forincreasing the amount of renewable energy used.
• The use of system temperatures close to room temperatures
will increase the possibility for using renewable energysources.
• This can be obtained by using large surfaces for theexchange of heat with the room like floors, walls andceilings

CONCEPTS OF RADIANT HEATING AND
COOLING SYSTEMS• Minimum 50% heat exchange by radiation• Heating - cooling panels• Surface systems• Embedded systems• Most recent development is the increasing
application world wide.

System types
Different installation concepts(thermally coupled or insulated form the building structure)21

Cooling panels

Suspended cooled ceilings

Capillary Tubes

Ceiling panels

18/10/2018

Bjarne W. Olesen, ICIEE-DTU

24

De-centralized systems
Fan-coil unit

Air - water systems for cooling
Cooled ceiling

Chilled beam

Built-ininduction unit