Solar hot water panels generally pass water or another heat
exchange liquid through dark tubes to absorb heat from direct
sunshine. The more efficient panels now use well designed
reflectors and evacuated glass tubes to maximise the heat
gain. With a solar boiler or tank, the heat can be exchanged
with the domestic hot water supply pipes. If you are building
a new home, the ideal system is solar hydronic slab heating.
A second coil in the solar boiler can be pumped via a control
manifold though embedded hydronic heating pipe coils in the
slab. Both the domestic hot water and hydronic heating water
can be backed up with a high efficiency instantaneous gas
booster. This set-up is the lowest carbon producing form of
hot water and space heating. If the slab is an exposed aggregate
finish (the most resource efficient) or other masonry finish
such as stone or tiles, inside north facing windows then the
direct passive solar gain does most of the heating.
Llewellyn Pritchard, Director
of Conscious Homes is an ESD consultant, registered Architect,
a registered Builder (Domestic Unlimited and Commercial Unlimited),
an HIA Greensmart Builder and writer. Conscious Homes won the 2006
National
HIA Greensmart Resource Efficiency Housing Award.
