Sustainable architecture
The design of the new office building of Energinet.dk has been
based on three overall environmental objectives:
- Local disposal of rainwater (LAR) resulting in a reduced load
on the sewage system and reduced water consumption.
- Making use exclusively of materials that ensure a good indoor
climate, small environmental impact and a minimum of
maintenance.
- Low energy consumption and reduction of CO2 emissions.
Henning Larsen Architects has designed a low-energy building
solely by means of optimising the design and an geometry -
resulting in an office building in the lowest energy class
possible. The building has an energy consumption of only 47,7
kWh/m2 a year. Incorporating solar panels, ground water cooling and
heat pumps in the project would further reduce the annual energy
consumption to only 35 kWh/m2. The building meets the requirements
for low-energy class 1 according to Danish building regulations
without the use of energy producing technologies.
The design is based on the integrated energy design concept
where the building is designed to achieve the lowest energy class
possible - and thus the lowest possible maintenance and operation
costs. In order to reduce the energy consumption of the building,
the design team has focused on:
Shape and orientation: A compact building (large
volume compared to surface area) reduces the heat loss and use of
materials
Functional positioning: The energy consumption can
be reduced significantly by means of a proper positioning of the
various functions of the building. Permanent workstations are
placed to the north-west and north-east to avoid overheating and
blinding.
Daylight optimisation: By testing different
daylight scenarios, the use of light and heat from the sun is
optimised and the use of artificial lighting is reduced. Tailoring
the light to the specific needs further optimises the use of
artificial lighting. In the design process, light simulations have
been applied to optimise the design and reduce the energy
consumption for artificial lighting and cooling.
In the design process, a comfortable inflow of daylight has been
ensured by means of the following:
- Permanent sunlight protection on the facades to avoid a direct
inflow of daylight and overheating.
- Indirect inflow of daylight from overhead lights in the
atrium.
- Direct sunlight from the west in summer in the cafeteria and
conference rooms. During the rest of the year, the rooms are in
shadow.
The offices feature three-layer low-energy windows and, in some
places, north-facing overhead lights. The offices only have direct
sun from the west in summer. For the rest of the year, the rooms
are in shadow.
The building has a green roof serving several sustainable purposes:
It reduces the load on the public sewage system by means of slow
percolation and evaporation. In addition, the collected rainwater
is used for flushing the toilets and watering the garden, which
contributes to reducing the overall energy consumption for
cooling.