Figure 1. The Bo01 System: 100 Percent Locally Renewable Energy.
Source: E.ON Värme Sverige.
homes and businesses is supplied by the
Aktern heat pump plant, in combination
with the natural underground water reservoirs and, to a lesser extent, seawater
(fig. 1). In the Western Harbour, there are
10 ‘cold’ and ‘hot’ wells drilled in an
aquifer at a depth of 40-70 m (131-230 ft).
The water in the aquifer, which maintains
a stable temperature of 10-11 degrees C
( 50-51.8 F) year-round, is used to store
heat from the summer and cold water
from the winter for seasonal use.
The heat pump collects heat either
from the district cooling return pipe or
the aquifers. The cooling resulting from
the heat extraction process can either be
delivered directly to the cooling network
or stored in the cold area of the aquifer.
The aquifer system can also be operated
in reverse, with the aim of delivering
cooling, at which time the heat is either
stored in the aquifer or supplied to the
city’s district heating network. When the
ocean is cold enough, the seawater serves
as an additional resource for the extraction of cooling.
The district cooling produced by the
heat pump system is used mainly outside
the Bo01 district, primarily in commercial
buildings elsewhere in the Western Harbour
development. Only four dwellings inside
the Bo01 district are connected to the
district cooling system, which features a
2. 4 MW and a 3.0 MW chiller. (In Sweden
it is highly unusual for residential homes
to use air conditioning.)
The balance of heat production ( 15
percent) is supplied by 1,400 sq m
( 15,069 sq ft) of solar collectors located
on top of 10 private buildings. Of these
solar collectors, 200 sq m ( 2,153 sq ft)
are vacuum collectors; the others, the
flat-panel variety. The solar collectors
are directly connected to the district
heating system, precluding the need for
bulky heat storage tanks in the buildings
and virtually eliminating the risk of
overheating.
The district energy network
includes four separate piping systems
for surface water, groundwater and for
the distribution of district heating and
cooling. The surface water circuit takes
in seawater through heat exchangers
and pumps it back out to sea. It is used
to cool the warm side of the chillers
between April and October and to produce natural cooling from November
through March. The groundwater circuit
is used throughout the year to pump the
cold and hot water stored in the wells in
the aquifers.
Electricity for the homes, the heat
pump and other area needs is generated
by a large 2 MW wind turbine located in
the Northern Harbour and 120 sq m
( 1,292 sq ft) of photovoltaic cells installed
on a building and directly connected to
the electricity network.
Annually, the Bo01 system optimally
produces 5,800 MWh of heat; 5,000 MWh
of cooling; and 6,300 MWh of electricity.
It is designed to serve 85,000 sq m
(915,000 sq ft) of space.
In Balance
The 100 percent renewable energy
Lively, Livable and Green
The Bo01 district of Malmö’s Western Harbour was designed to be environmentally
sustainable, for certain, but also to be attractive in its own right. Planners aimed to
create a neighborhood where people would want to live for its inherent qualities. The
result is a modern urban quarter characterized by an exciting diversity of architectural
styles (courtesy of 22 different architects) connected via a network of individually
designed streets, narrow alleyways and pedestrian walks to beautiful spaces for the
public to enjoy. Parks, open squares, a beach and seafront promenade all invite residents and visitors to come for a stroll or cultural happening.
A showcase of environmental sustainability, the Bo01 area boasts numerous green
features in addition to its energy system. A stormwater runoff system collects rain
water on green roofs, in courtyards and public spaces to sustain a lush landscape of trees
and plants. Apartments are connected to an organic waste disposal system that turns
food waste into sludge, eventually transformed into biogas to fuel vehicles. Inhabitants
are encouraged to walk, use bicycles or public transportation, with a bus stop within
300 m (984 ft) of the homes and only 0.7 parking spaces in the district per household.
Although the Bo01 district occupies just 12 percent of the Western Harbor, it serves as
an ambitious example of ecological and social sustainability for the rest of this bustling,
growing area of Malmö to follow.
