Collective housing

1. Heat pumps and district heating

                                                                                                     Photo: star-ref.co.uk

This is Drammen District Heating in Norway. Drammen Fjernewarm. They operate a 45MW district heating system serving over 200 large buildings in the city. The heat was originally from a mixture of fossil fuel and biomass but a new system was designed to make a large heatpump the primary source.

They now draw 75% of the network heat from the ammonia heatpumps at 90C with 15% from biomass and 10% from gas/oil. From the new building shown here 85% of the heat is from the heatpump. Roughly 67GWh per year and over 150GWh since installed in 2010. (summer of 2014).

What was implemented

                                                                                                        Photo: bbc.co.uk

This is the system put in place by Star Refrigeration. It draws water from the fjord at 8C and cools it to 4C. The heatpump boosts this energy up to 90C and delivers 13.2MW. It is believed to be the largest system in the world operating at these temperatures and definitely the largest doing so using ammonia as the working fluid. Good news as a 1% leakage of the alternative R134a would have been the equivalent of driving 800000km in a car every year in global warming. Using ammonia also increased the COP by around 25% - vital in ensuring maximum return on investment for heatpumps.

Environmental savings:

  • 6 700 000 litre of fossil fuel per year
  • Natural refrigerant Ammonia: GWP & ODP = 0
  • CO2 reduction: 12 663T per year
  • 101 million km driving equivalent per year

Financial savings:

System COP: 3,05 at 90C, that saves €4m per year vs fossil fuel

2. Heat pumps for hotel and school

                                                                                              Photo: travel-swiss.co.uk

This is Bradutt's Palace in St Moritz, Switzerland. They had a great demand in heating and hot water for themselves, but also for the local primary school located just beneath

What was implemented

This is the system put in place by Mayekawa to provide heating and hot water to the hotel and the school.

                                                                                                       Photos: Mayekawa

Amonia stage 2 heat pump

Environmental savings:

  • 400.000 liter of fossil fuel per year
  • Natural refrigerant Ammonia: GWP & ODP = 0
  • Recovery lake natural temperature level
  • CO2 reduction: 1200T per year

Financial savings:

  • System COP: 3,19, that makes 232.000 CHF (190 901,07 euro) less on yearl energy bill
  • Return on investment: less than 2 years
  • Investment - life cycle : more than 20 years.

3. Heat pumps for communal building

A luxury development in central London uses air source heat pumps to provide heating, cooling and hot water to 42 apartments and 3 penthouses.

What was implemented

                                                                                                                             Photo: daikin.co.uk

Based on a energy assessment, the Daikin Altherma Flex air-to-water heat pumps were chosen, opposite to the ground source ones. This provided better energy efficiency with a lower construction risk associated with an open loop ground source installation. As a result, 6 heat pumps with 45 kW power each were installed, connected to the underfloor heating of the building, delivering the heat at 45oC. The system is a modular one, and is suitable for multi-occupancy projects.