PROPOSAL:

Execute Contract to Cost-Share Development and Demonstration of High-Efficiency, Solar Energy-Based Air Conditioning Technology

SYNOPSIS:

Bergquam Energy, Sacramento, CA has proposed developing and demonstrating a commercial-size solar energy-based air conditioning system. The objective of the proposed project is to substantially improve the efficiency and the commercial feasibility of solar energy air conditioning technology using state-of-the-art solar collection and gas-absorption chiller technologies. Total cost of this project is $607,400, with a proposed AQMD cost-share of $75,000.

COMMITTEE:

Technology, June 27, 1997, Recommended for Approval

RECOMMENDED ACTION:

Authorize the Executive Officer to execute a contract with Bergquam Energy, for an amount not to exceed $75,000, to cost-share development and demonstration of a 20-ton commercial-size, solar energy-based air conditioning system.

James M. Lents, Ph.D.
Executive Officer

Background

Air conditioning in the residential and commercial sectors represents up to 30% of the electricity load during hot summer days that are also periods of peak ozone concentration in the Basin. Such demand places a heavy strain on the electricity production and distribution network. Control of NO_x emissions from power plants that generate electricity to meet these summer air conditioning loads are required under RECLAIM, Rule 1135 and Rule 1134. The development and commercialization of solar air conditioning systems could substantially reduce electricity loads and the associated power plant emissions of criteria and greenhouse pollutants.

Early attempts in the 1970s to develop solar air conditioning systems failed. Since then, significant progress has been made in the development of key components of this
technology. For example, the efficiencies of solar collection technologies have considerably improved; gas-fired absorption chiller technologies have been developed and commercialized; and refrigerant technologies using water-based solutions, such as lithium bromide salt solutions, have shown potential to replace conventional air conditioning refrigerants such as CFCs.

Proposal

Large industrial and commercial buildings are beginning to use natural gas absorption chillers in place of electricity-driven chillers for their air conditioning needs. Small commercial buildings, however, almost exclusively use electrically-driven air conditioners to provide their cooling needs. The proposed project will address the latter segment. The project will develop and demonstrate a 20-ton solar air conditioning unit using state-of-the-art solar energy collection technology, gas-absorption technology, and CFC-free refrigerant technology.

In the proposed project, Bergquam Energy will build on their previous successful effort in designing, integrating and testing conventional solar collection technology with a "single-effect" absorption chiller. In this previous work, solar heat was provided by an array of conventional flat-plate collectors, and an array of parabolic-trough concentrating collectors. Moreover, a detailed evaluation was conducted to develop a design of a "double-effect" solar absorption chiller that has substantially higher efficiencies than a "single-effect" a solar air conditioner. A double-effect chiller, using 165 degree Centigrade thermal energy input, almost doubles the coefficient of performance (COP) to 1.2 from a COP of 0.65 for a single-effect chiller that uses 110 degree Centigrade thermal input.

The proposed project will further refine this design, develop detail drawings, and construct and test the world's first "double-effect" solar air conditioner. It proposes to use an advanced solar collection system, known as the Integrated Compound Parabolic Concentrator (ICPC) array. A 20-ton, natural gas-fired double-effect absorption chiller will be modified to run on hot water from the ICPC collectors. A heating, ventilation and cooling system (HVAC) will be designed to run on the above modified chiller with the ICPC collectors. The complete system will be installed and tested on an 8,000 square foot commercial building in Sacramento owned by Bergquam Energy. This building is fully instrumented to characterize and measure the operating data of the proposed system. If successful, the system will be dismantled, shipped, and reassembled in a facility in the City of Palm Springs for a follow-up demonstration. In addition, the Contractor will develop a preliminary design for a much larger 100-ton solar air conditioning unit. The contractor will also conduct a market assessment and identify potential sites for mass commercialization of these units.

The proposed project is included in the October 1996 update of the Technology Advancement Plan for the Clean Fuels Program as proposed project S2-2, "Development and Demonstration of Clean Energy Alternatives for Stationary Power Generation." The primary benefits of this project are expected to occur over the long term. If proven successful, solar air conditioning units could substantially reduce NO_x, SO_x and greenhouse gas emissions by significantly reducing the use of electricity generated by fossil fuel-fired power plants needed to run conventional air conditioning units. This would lower the electricity demand during peak summer ozone days and, potentially, reduce the long-term need to construct expensive electric power plants and transmission lines.

Sole Source Justification

Section II, Step 3(C) of the Consultant Selection Policy and Procedure, identifies four provisions under which the Executive Officer may award a sole-source contract: (1) cost to prepare documents exceeds cost for consultant; (2) delay would result in the endangerment of public health; (3) services are only available from sole-source; and (4) other circumstances exist identifying sole-source as in the best interest of the AQMD. This request for sole-source award is made under provision (3).

The proposed project includes several elements that make it unique and are only available from Bergquam Energy and its project team. As described in detail below, the assembled team is uniquely qualified and brings into the project state-of-the-art university research, advanced solar technologies, a manufacturer of absorption chillers, and significant direct cost-sharing from other funding sources.

(a) Bergquam Energy, Sacramento, CA. Bergquam Energy is the only company in the country that has successfully constructed and operated a durable, solar energy-based, air conditioning unit using gas-absorption technology. Bergquam Energy has been active in the development of solar cooling technology for over 15 years. The firm has worked on components, sub-assemblies and complete systems from concept and design, to installation, operation and ongoing testing.

Previous efforts demonstrated the technological feasibility of solar air conditioning. The proposed project will build on past efforts to significantly improve the efficiencies of solar air conditioning and the economics of this technology. The availability of high-efficiency, advanced solar collectors, gas-absorption chillers, and CFC-free water-based refrigerant technologies are expected to contribute to the success of the proposed project.

(b) Solar Enterprises International (SEI). Dr. Roland Winston is the principal participant at SEI and a leading pioneer and highly regarded author in the advanced field of non-imaging optics. Dr. Winston invented the non-imaging concentrator known as the integrated compound parabolic concentrator (ICPC). These stationary concentrators, designed in the form of evacuated tubes, collect and intensify solar radiation far better than conventional lenses, mirrors, flat panels and parabolic concentrators. Dr.
Winston's technology, to be used in the proposed project, is expected to substantially improve the conversion of solar energy into useful heat energy.

(c) McQuay Inc. McQuay, Inc., a national manufacturer of commercial-size air conditioning units, developed and is now commercializing 20-ton natural gas-fired absorption chillers. Moreover, McQuay has refined the use of brine as a refrigerant in these chillers in place of conventional CFC refrigerants, which are ozone depleting compounds. McQuay will provide this advanced 20-ton chiller for the proposed project in which solar thermal energy will substitute for the natural gas burner. McQuay will also provide technical assistance in modifying its chiller to operate on solar energy.

(d) City of Palm Springs. The City of Palm Springs has offered to host the demonstration at a fire station facility. This facility is 5,000 square feet in size, and requires cooling 24 hours a day, 7 days a week during summer months.

(e) Significant Direct Cost-Sharing. As listed below, Bergquam Energy has already obtained approximately 85% of the funding from other sources.

Resource Impacts

The total cost of this project is estimated to be $607,400. The breakdown of the co-sponsors and estimated support is as follows:

Sufficient funds are available in the FY 1997-98 Budget to cosponsor this project in an amount not to exceed $75,000.

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