SOLAIR Pty Ltd recommends the use of solar air collectors in buildings
to enable significant savings on energy consumption and carbon emissions.
The air conditioning system accounts for about 50 per cent of a
building’s energy consumption with the balance going towards other services
such as common area lighting, domestic hot water and lifts. Therefore, any reduction
in air conditioning energy consumption or ensuring efficient energy utilisation
will lead to significant savings in total building energy consumption and
carbon emissions.
Such buildings should adopt night purging, displacement ventilation, positive
input ventilation with 100% fresh air intake using solar air collectors, high
thermal mass materials and a co-generation plant to significantly contribute to
the health of occupants, and reduce carbon dioxide emissions as well as energy
consumption. Implementing all of these initiatives will reduce carbon emissions
to 44% of a 4.5 star Australian Building Greenhouse Rated building.
Using a thermal (solar air collector) panel system for both night purging
for cooling and daytime solar absorption for heating introduces 100% fresh air
into the building, thereby flushing out all contaminated air without mixing. Key
benefits include enhanced air quality, health wellbeing and productivity of all
occupants as well as significant reduction in maintenance costs from minimal
hourly use of boilers/chillers.
As most large-scale buildings are built on concrete and other reasonably
good thermally absorbing materials, they are capable of storing and releasing
large amounts of energy (sensible heat). In summer, the building will store the
coolness of the night and use it to cool the building during the day. Conversely,
in winter, the building will absorb solar heat energy during the day and use it
to maintain higher core temperatures at night.
Thermal mass, when correctly used, moderates internal temperatures by
averaging out diurnal extremes; incorrect use can exacerbate the worst extremes
of the climate and become a huge energy and comfort liability.
A ‘green’ building aims to minimise the emission of greenhouse gases,
namely carbon dioxide emissions through efficient energy usage, and is based on
effective energy utilisation between sources such as electricity, gas, solar,
wind or energy from a co-generation plant.
Key advantages of thermal passive input ventilation systems include reducing
CO2 emissions to 40% in a 4.5 star building; enhanced air quality by providing
100% fresh, non-recycled air; equal access to all occupants to the cool ceiling
above and floor vents evenly distributed to passively provide a more even
temperature throughout the space; and increased productivity through the
reduction of noise, enhanced air quality, and even distribution of cool air in
addition to healthier and more comfortable occupants.
Buildings using thermal passive input ventilation systems can also
reduce maintenance costs from using a system with less moving parts. The lifespan
of the chilled night flush system is also extended because of reduced plant
loads and less maintenance problems. The thermal heat and night flush systems
eliminate the need for additional internal high volume ductwork, minimising
ceiling voids requirements and increasing opportunities for refurbishment as
well net leasable area opportunities. All solar air collector systems can be
retrofitted and adapted to existing air ventilation systems.
Solar air collectors are highly energy efficient with friction losses
and lagging eliminated by the system and the building fabric contributing to
the cooling system. With solar air collectors, all daytime air has the enormous
benefit of dehumidification, greatly reducing the possibility of increased
condensation.
A building can also save more energy by using secondary external shading
to Northern/ Western walls, thermal (light colour) paints and external
screening/shading to glazed areas.