Page 176 - Alternative Energy Systems in Building Design

152 SOLAR POWER SYSTEM PHYSICS AND TECHNOLOGIES

■ Conduct an energy audit.
■ Provide detailed data about site topology and present and future land use.
■ Provide data regarding local climatic conditions such as wind, sand, or dust accu-
mulation and cyclic flooding conditions, if applicable.
■ For roof-mount systems, provide aerial photographs of roof plans that show mechani-
cal equipment, air vents, and roof hatches. Drawings also must accompany architec-
tural drawings that show parapet heights and objects that could cause shading.
■ Specifications should outline current electrical tariff agreements.
■ The document also should incorporate any and all special covenants, conditions,
and restrictions associated with the leased property.
■ To ensure system hardware reliability at the posterity of the contract, the RFP must
include a generic outline of hardware and data-acquisition and monitoring software
requirements.
■ The specifications must request providers to disclose all issues that may cause
noncompliance.
■ Expected power output performance guarantees, as well as projected annual power
generation requirements, must be delineated.

Owners are also advised to conduct preliminary renewable-energy production
studies that would enable them to evaluate energy-production potential, as well as
economic analysis of possible alternatives.

PPA contract structure for solar power systems To prepare a PPA request
for a proposal document, the owner’s legal counsel and management personnel must
familiarize themselves with various elements of the contract agreement. Agreements
involving third-party ownership consist of two parts, namely, legal and technical. The
following are some of the most significant points of PPA-type contracts that third-
party purchase providers must respond to and evaluate accordingly:

Contractual matters of interest
■ DC output size of the PV modules in kilowatthours
■ AC or PTC output of the PV modules in kilowatthours
■ Expected ac power output of the solar system in its first year of installation
■ Expected life-cycle power output in kilowatthours dc
■ Expected life-cycle power output in kilowatthours ac
■ Guaranteed minimum annual power output performance in kilowatthours ac
■ Terms of contractual agreement
■ Penalty or compensation for performance failure
■ Price structure at the end of the contract with client paying 0 percent of the cost
■ Price structure at the end of the contract with client paying 50 percent of the cost
■ Price structure at the end of the contract with client paying 100 percent of the cost
■ Expected average yearly performance during life cycle of the contract
■ Expected mean yearly performance degradation during life cycle of the contract
■ Assumed PPA price per kilowatthour of electrical energy
■ Initial cost of PPA