General Project Description
A 1MW AC photovoltaic carport farm was constructed on the Northwest Parking Lot at the East Los Angeles Community College (ELAC) campus to provide green and renewable energy to meet part of the campus’ power needs. The carport farm consists of seven steel carport structures, running east to west, supporting 5,952 photovoltaic panels which were installed with a 2-degree tilt to the south, to maximize solar irradiation. Each carport structure is of a “T” shape design, with supporting columns running in the mid-span of the carport canopy, which shades a double parking row.
The photovoltaic panels were manufactured by Kyocera. Each panel can produce about 200W DC at peak solar irradiance. The panels are circuited in series into “strings”, which are terminated in a combiner box at each carport structure. From the combiner boxes, electrical power is transmitted through underground conduits to two inverters manufactured by Satcon, which convert the DC power to AC. The AC power is then stepped up to 4160V and fed into the existing College electrical grid.
The photovoltaic carport farm is estimated to produce about 1.5 Million kWh per year, enabling the College to obtain about 40% of its electrical energy from a green, sustainable, and emission free energy source. In addition, the carport structures add shading to about 530 parking spaces, and provide improved parking lot lighting from the new, energy efficient fixtures mounted at the underside of the canopy.
Goals and Visions
The Los Angeles Community College District (LACCD) is the largest community college district in the United States. It covers an area of more than 882 square miles with nine colleges serving more than 36 cities and communities.
The District is currently undertaking the largest public sector green building program in the U.S., funded by a $2.2 billion bond program. The District intends to decrease its dependence on fossil fuels and increase energy efficiency in all of its buildings. In October 2006, the District announced a plan to be the first community college district in the nation to self-generate power for all of its energy needs. This ambitious plan to “go off the grid” establishes LACCD as a national leader and model for sustainability among community college districts. The District’s 9-MW Renewable Energy Plan calls for the installation of solar photovoltaic power systems to produce at least one megawatt of electricity at each of its nine colleges – enough to meet a substantial portion of campus daytime electricity needs.
East Los Angeles College (ELAC) is the first LACCD campus to install one megawatt of solar power. ELAC selected Chevron Energy Solutions (CES), a unit of Chevron Corporation, to design and install the system at its campus in Monterey Park, California. CES also assisted the College in arranging project financing with MMA Renewable Ventures, a third-party partner. MMA Renewable Ventures paid for the design and construction work performed by CES and in turn owns and sells power from the photovoltaic system to the College under a 20-year Power Purchase Agreement (PPA), which sets the electricity rates for each year throughout the contract term. This takes away the risk of drastic and unpredictable electricity rate fluctuations that the College would otherwise encounter, for a significant portion of its electricity needs. After seven years, the District has the option to purchase the photovoltaic facility from MMA Renewable Ventures.
The photovoltaic carport farm is the first solar energy installation on the ELAC campus. Throughout the design and construction phases, information about the project and the photovoltaic technology was communicated to the staff and student body, through meetings, student paper interviews and other publications. In addition, a kiosk has been installed in the Technology Center on campus to display real time electricity production data. Project details are also shared with other LACCD colleges, and there has been high public interest as well.
The photovoltaic carport project idea was developed in 2006, and soon after, partners were identified to provide the design, financing and construction services. The PPA arrangements were finalized while the structural and electrical design was done. The engineering package was then reviewed by College personnel to ensure that it would meet College design standards and needs. After the engineering design package was finalized, it was submitted for technical review at the Division of State Architect (DSA).
At the same time, to secure photovoltaic panel and equipment availability and pricing, efforts were expensed in arranging the purchase and delivery of the photovoltaic panels, inverters, structural steel and other system components. CES also worked diligently with the College to determine a construction phasing plan, in an effort to minimize the negative impact to the parking situation on campus. Once DSA approval was obtained, construction began in earnest and proceeded at a very fast pace so that the entire parking lot could be reopened at the earliest possible date. Safe construction practices were, however, always observed, and remained the primary focus of the construction crew.
CES also applied for, on behalf of the College, rebate from the Self Generation Incentive Program (SGIP) administered by the Southern California Edison Company (SCE). This incentive program provides monetary incentives for renewable self generation energy systems. The ELAC system was eligible for about $3 Million worth of incentive.
The photovoltaic carport project was completed in about 4 months, with no safety incidents, and the College had access to about half of the parking spaces throughout the construction period. Construction progress was communicated to SCE periodically, and inspections were scheduled and conducted promptly to secure project acceptance by SCE in advance of the SGIP deadline. The SGIP incentive helped in reducing the project cost for ELAC.
Special Challenges and Innovative Solutions
A public institution cannot take advantage of government tax incentives and accelerated depreciation for photovoltaic systems. In order to capture these financial incentives to help lower the overall project cost, a financial solution was devised, via a Power Purchase Agreement (PPA), to bring in a private enterprise to provide funding for the photovoltaic carport project.
The private enterprise, MMA Renewable Ventures, through tax incentives, rebates and access to investor capital, essentially paid for the design and construction of the project so that LACCD and ELAC did not need to provide any capital outlay. Only after the system came online would ELAC need to pay for the electrical power, at a rate comparable to what the utility company would charge, and only for the electricity generated by the photovoltaic system. At the end of the PPA term, the ownership of the photovoltaic carport system will go to the College at no cost. And thereafter, the College will enjoy free power from the photovoltaic system.
The College also has the option to purchase the system outright after seven years, when the accelerated depreciation period is over. Once purchased, the College will no longer need to pay for the electricity generated from the photovoltaic system.
With a PPA arrangement, this project is a successful example of public and private interests working together to achieve mutual benefits:
ELAC is guaranteed a minimum level of power output from the photovoltaic system.
ELAC pays only for the power produced with no capital or operating costs.
LACCD is able to plan its energy budget accordingly while enjoying significant cost savings.
LACCD is provided with a big step forward to reach its sustainability goals.
Private financing arrangement allows LACCD to use bond money to pay for other energy infrastructure upgrade projects and new green building construction.
Installation serves as a model for students to study practical applications of green technologies.
The Northwest Parking Lot at ELAC was an open lot with no shaded parking. The parking rows are arranged in an east-west direction, and the ground slopes to the south. This configuration provided an ideal arrangement for the carport structures as it allowed panels to be arranged and tilted to the south, maximizing solar irradiance. There is also an electrical manhole close by, where the connection to the campus power grid is made, minimizing the amount of trenching required.
The photovoltaic panels are of the multi-crystalline type, among the most efficient in panels available today. The system converts solar energy into electricity, with no moving parts and generating no noise and pollution. The inverters installed have an efficiency of 95%, minimizing conversion loss.
The PPA arrangement allows the project to benefit from the tax incentives and thereby lowers the overall project cost. The financial terms work out such that ELAC will not incur a higher electrical utility cost than what it has been paying. And with escalation rates fixed on the PPA, ELAC also enjoys predictable energy costs throughout the next 20 years.