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Heliostat for Residential Heating and Lighting |
Category: Sustainable Technology |
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Rob Steves
Richmond, BC CA
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Page Views: 397
Votes: 11
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Entered: 08/13/2008
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A
heliostat
is
a
device
that
orients
a
mirror
to
reflect
sunlight
continuously
onto
a
desired
target.
Heliostat
technology
has
been
used
for
commercial
power
plants
of
10MW
and
more
and
occasionally
on
a
residential
scale
for
water
heating
applications.
Two
years
ago
I
had
the
idea
to
utilize
the
same
technology
to
provide
direct
home
heating
and
lighting
by
reflecting
sunlight
continuously
into
north
facing
windows.
Such
a
heliostat
might
consist
of
a
flat
mirror
(or
silvered
mylar
stretched
taught
between
a
frame
to
reduce
the
weight),
attached
to
a
gimbal
mount
with
rotation
and
tilt
controlled
by
stepper
motors.
Tracking
software
could
be
integrated
with
the
stepper
motor
controllers,
or
an
external
computer
could
be
used.
I
built
a
prototype
with
a
mirror
area
of
4'x7',
positioned
by
two
stepper
motors
controlled
from
a
laptop
in
my
home.
I
have
used
the
prototype
successfully
for
supplemental
heating
and
lighting
in
my
own
home
for
the
last
two
years.
See
attached
website
links
and
images.
Potential
benefits
to
homeowners
are
reduced
carbon
footprint,
cost
savings
over
heating
by
fossil
fuels
alone,
and
ample
natural
light
to
rooms
that
currently
receive
little
direct
sunlight.
A
residential
heliostat
offers
heating
capabilities
similar
to
more
common
flat
panel
solar
thermal
collectors.
However
a
heliostat
can
collect
about
twice
the
energy
per
unit
area
compared
to
a
flat
panel
collector.
This
is
because
the
conversion
from
full
spectrum
sunlight
to
long
wavelength
infra
red
(heat)
occurs
inside
the
home
rather
in
a
panel
outside
the
home
where
much
of
the
heat
is
invariably
lost
to
the
surroundings.
The
ability
to
track
the
sun,
capturing
early
morning
and
late
evening
sunlight
also
accounts
for
higher
energy
capture.
If
manufactured
in
quantity,
the
cost
of
a
residential
heliostat
could
be
similar
(per
unit
area
of
collector)
to
that
of
flat
panel
solar
thermal
designs.
However,
given
the
greater
energy
capture,
the
time
to
payback
would
be
much
shorter.
No
modification
to
the
home
is
required.
Installation
could
be
as
easy
as
installing
a
satellite
dish.
Heliostats
are
also
quite
pretty
by
comparison
to
flat
panel
solar
thermal
collectors.
To
my
knowledge,
this
idea
is
novel
in
the
sense
that
heliostats
have
never
been
offered
commercially
for
use
on
a
residential
scale.
Advances
in
motors
and
electronics
have
only
recently
reduced
costs
to
the
point
where
such
a
design
is
economically
feasible.
The
market
for
such
a
product
is
the
same
as
that
of
flat
panel
solar
thermal
technology.
There
are
no
major
technical
challenges
to
overcome.
While
there
is
still
a
large
benefit
to
installing
such
a
system
for
existing
homes,
the
greatest
benefit
could
be
achieved
by
designing
homes
to
take
advantage
of
heliostat
technology.
Such
homes
would
have
relatively
small
north
facing
windows
and
multiple
heliostats
to
reflect
sunlight
through
these
window
onto
a
large
thermal
storage
and
distribution
medium
(for
example
a
brick
wall
or
water
tank).
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Tags for entry:
solar
heliostat
thermal
residential
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Meet the Entrant, Rob Steves
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Profession: Engineer/Designer |
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My Website: http://www.iwilltry.org... |
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My Heliostat Page: http://www.iwilltry.org/w/index.php?title=How_to_build_a_heliostat_for... |
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Number of times entering contest previously: 0
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Design Tools:
Pencil and Paper
Physical models
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Rob's favorite design tool:
Excel. Data analysis and process modeling are essential for optimizing a design. In that regard, there's almost nothing that can't be done in Excel.
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Rob's hobbies and activities:
tinkering in the shop, improving my home, camping, ultimate frizbee
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What role does Rob believe product design plays in creating a better future?
Very little. "Better" to me means happier, but a people's happiness is not related to products or technologies, or if it is it's an inverse relationship. Products are created to meet "wants", not "needs". Giving (or rather selling) people what they want will seldom lead to their happiness.
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Hardware used for design:
Dell
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