Internal absorber solar collector

Patent · Thu Jan 01 00:00:00 EST 1981

OSTI ID:864082

Sletten, Carlyle J ^[1]; Herskovitz, Sheldon B ^[2]; Holt, F S ^[3]; Sletten, E J ^[4]

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1. 106 Nagog Hill Rd., Acton, MA 01720
2. 88 Hammond St., Acton, MA 01720
3. 46 Emerson Rd., Winchester, MA 01890
4. Chestnut Hill Rd. R.F.D. Rte. #4, Amherst, NH 03031

Thin solar collecting panels are described made from arrays of small rod collectors consisting of a refracting dielectric rod lens with an absorber imbedded within it and a reflecting mirror coated on the back side of the dielectric rod. Non-tracking collector panels on vertical walls or roof tops receive approximately 90% of solar radiation within an acceptance zone 60.degree. in elevation angle by 120.degree. or more in the azimuth sectors with a collector concentration ratio of approximately 3.0. Miniaturized construction of the circular dielectric rods with internal absorbers reduces the weight per area of glass, plastic and metal used in the collector panels. No external parts or insulation are needed as heat losses are low due to partial vacuum or low conductivity gas surrounding heated portions of the collector. The miniature internal absorbers are generally made of solid copper with black selective surface and the collected solar heat is extracted at the collector ends by thermal conductivity along the absorber rods. Heat is removed from end fittings by use of liquid circulants. Several alternate constructions are provided for simplifying collector panel fabrication and for preventing the thermal expansion and contraction of the heated absorber or circulant tubes from damaging vacuum seals. In a modified version of the internal absorber collector, oil with temperature dependent viscosity is pumped through a segmented absorber which is now composed of closely spaced insulated metal tubes. In this way the circulant is automatically diverted through heated portions of the absorber giving higher collector concentration ratios than theoretically possible for an unsegmented absorber.

• Research Organization: Solar Energy Technology, Inc., Bedford, MA
• DOE Contract Number: FG04-77CS34163
• Assignee: Sletten, Carlyle J. (106 Nagog Hill Rd., Acton, MA 01720);Herskovitz, Sheldon B. (88 Hammond St., Acton, MA 01720);Holt, F. S. (46 Emerson Rd., Winchester, MA 01890);Sletten, E. J. (Chestnut Hill Rd. R.F.D. Rte. #4, Amherst, NH 03031)
• Patent Number(s): US 4307709
• OSTI ID: 864082
• Country of Publication: United States
• Language: English

Related Subjects

internal
absorber
solar
collector
collecting
panels
described
arrays
rod
collectors
consisting
refracting
dielectric
lens
imbedded
reflecting
mirror
coated
non-tracking
vertical
walls
roof
tops
receive
approximately
90
radiation
acceptance
zone
60
degree
elevation
angle
120
azimuth
sectors
concentration
ratio
miniaturized
construction
circular
rods
absorbers
reduces
weight
glass
plastic
metal
external
insulation
heat
losses
due
partial
vacuum
conductivity
gas
surrounding
heated
portions
miniature
solid
copper
black
selective
surface
collected
extracted
thermal
removed
fittings
liquid
circulants
alternate
constructions
provided
simplifying
panel
fabrication
preventing
expansion
contraction
circulant
tubes
damaging
seals
modified
version
oil
temperature
dependent
viscosity
pumped
segmented
composed
closely
spaced
insulated
automatically
diverted
giving
ratios
theoretically
unsegmented
solar heat
concentration ratio
partial vacuum
absorber rods
reflecting mirror
temperature dependent
heat loss
solar collector
thermal conductivity
thermal expansion
solar radiation
closely spaced
metal tube
vacuum seal
metal tubes
collector panels
vertical wall
heated portions
heat losses
roof top
rod lens
collected solar
collector panel
dielectric rod
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