The POWER ROOF is a new concept in solar
energy that has the potential to become a major force in the renewable
energy industry's market for industrial and large commercial buildings,
both in the United States and abroad. More significantly, because
of the system's integrated building approach and projected energy
cost savings potential, the POWER ROOF system will become
an attractive energy option for the large industrial and commercial
energy user. The system is designed for both new and existing facilities.
The POWER ROOF design is a total building system, which can
provide the buyer with lower energy bills, superior natural delighting,
and a more comfortable workplace. Equally important in today's world,
this energy option is essentially environmentally benign.
The POWER ROOF system integrates excellent
energy-efficient technologies with the most advanced solar concepts
known today. The POWER ROOF system is a high-temperature
solar collector, a natural delighting system, s radiant barrier,
an insulating system, and an optional means to capture passive
solar heat in the winter, an infiltration barrier, the structure,
and a waterproof guaranteed roofing system - all in one. Because
of these multiple functions, served by a single building system,
comparative construction costs to imitate the same advantages
are significantly greater. This obviously makes the POWER ROOF
system more competitive in the energy market.
Because of the system's extremely effective concentrating
powers, collection temperatures in excess of 750 degrees F are
possible. This energy can most appropriately be utilized in the
form of water purification, water pumping and desalination as
well as secondary space heating and domestic hot water uses. And,
where needed, it can also be converted to electricity for individual
facility requirements or sold to utility companies during times
of peak electrical demand.
The following advantages clarify the unique aspects
of the POWER ROOF system:
- The POWER ROOF is a roof system as well as an energy
saving system (picture 2.1). By taking an integrated approach,
the net installation cost is projected to be considerably less
than other solar thermal systems, which are almost entirely
ground mounted. The building-integrated POWER ROOF system
requires no additional land.
- Because of the POWER ROOF system's extremely high concentration
efficiency, the system is ideally suited for industrial process
heat applications and desalination, as well as for producing
- The POWER ROOF system utilizes a fixed reflective surface
and a tracking secondary receiver. This is opposite from the
typical solar thermal trough systems, which have a stationery
receiver and moving reflector. By moving the much smaller component
and fixing the larger reflector, the POWER ROOF system
has significant structural advantages and less associated maintenance.
- The industry standard for receivers evacuated glass tube
in which the fluid is circulated. The PWER ROOF system
utilizes a superior receiver, which incorporates an Integrated
Compound-Parabolic Concentrator within the solar industry and
produces a collection efficiency, which is higher than other
- The POWER ROOF system can be installed on individual
buildings, thereby reducing the efficiency losses associated
with control utility type systems and allowing it to be utilized
as distributed power including for remote and off-grid regions.
- The POWER ROOF system can be purchased incrementally,
as needed by the owner.
- Because our clients are typically building owners, the utility
rates which we are competing against are the higher rates charged
to our customers by utilities, not what the utility pays for
power generation and distribution.
- The POWER ROOF system is designed for both new and
existing facilities and can be incorporated into many types
of structures other than typical roof areas (i.e., covered parking
- The POWER ROOF system is environmentally sound.
- The POWER ROOF system provides building owners an energy
option, which helps them to make their energy future more secure.
- In addition to typical tax advantages associated with buildings
in the United States, the POWER ROOF system solar investment
tax credit. There are also many states the additional tax advantages.
The Clean Air Act also improves the cost benefits associated
with all solar energy options in the United States.
- The POWER ROOF is a total building system, which integrates
quality energy technologies with quality building technologies.
Because of the temperature ranges that are possible utilizing
the CPC in conjunction with the POWER ROOF design, many
markets not previously pursued by the solar thermal industry can
now be approached.
The POWER ROOF system has particularly significant cost
advantages for integrating the system into new buildings or roof
assemblies, but retrofit possibilities also exist where reproofing
cost can be saved or where limited real estate make this option
a viable solution. Designs that have been pursued with potential
customers range from POWER ROOF systems integrated into
greenhouse roof assemblies covered parking areas, and covers over
fresh water canals, as well as industrial and commercial buildings.
To meet particular energy needs, stand-alone systems may also
be practical solutions.
Power Roof Applications:
Industrial Process Heat
Power Roof Fact Sheet
The Power RoofTM system integrates the best
energy-efficient technologies with the most advanced thermal solar
energy systems known today. The tracking Power RoofTM is a south-facing
high temperature solar energy collector with a fixed reflector
and tracking integrated compound parabolic concentrating evacuated
tube receiver, and north-facing natural daylighting glazing. A
Power RoofTM module is sized for easy integration into standard
building designs. It includes a radiant barrier, an insulating
system, an optional means to capture passive solar heat in the
winter, an infiltration barrier, the building roof structure,
and a waterproof, guaranteed roofing system all-in-one. Because
of these multiple functions, served by a single assembly, comparative
construction costs to imitate the same advantages are significantly
The system's enhanced solar energy concentrating
feature enables collection temperatures in excess of 7500F in
suitable climates at efficiencies between 40% and 45%. This energy
can most appropriately be utilized in the form of steam for electric
power generation, industrial processes, double-effect absorption
cooling, desalination and water purification as well as secondary
space heating and domestic hot water uses. Until now, most solar
thermal energy systems were limited to lower temperature ranges
of 2120F to 2600F. Of the total industrial process heat market
in the US, temperature needs below 2120F (hot water) represents
only 1.5% and steam temperatures between 2120F and 3000F account
for an additional 16.5% of industry's needs. With the wide range
of collectors covering temperatures from 1000F to 7500F, Solargenix
Energy is capable of matching most thermal energy needs within
an industrial process application.
The first Power RoofTM system is now being constructed
adjacent to a Parker-Lincoln commercial office and warehouse building
located on Westinghouse Blvd. in Raleigh, NC, and it is expected
to be operational in January 2002. It has the following characteristics:
- Thirty-six 12 ft x 16 ft modules
- Vertical load per module: 10 lbs/sq.ft.
- Total collecting aperture area: 5,400 sq.ft.
- Heat transfer fluid: water
- Maximum operating temperature: 3500F
- Peak solar energy delivered to load: in excess of 500
- Energy use: space heating, service hot water, heat input
to 50-ton Yazaki 2E absorption chiller for space cooling, heat
input to 6 kW ORC turbine/generator.
- Full instrumentation and data acquisition system
The unique absorption chiller incorporates a newly
designed generator that can be fired by both natural gas and solar
heated hot water, so that a separate gas hot water boiler is not
needed to operate the chiller when solar energy inventories are
low or non-existent.
This first Power RoofTM installation will serve
as a test and demonstration system to study its operating characteristics
and to develop control strategies for building integrated HVAC
and power applications.