Photovoltaic research and demonstration activities at New EnglandElectric

From 1985 onward, New England Electric has carried out and supported a wide range of research, development and demonstration projects related to the use of solar photovoltaic (PV) energy. This paper describes each project and summarizes performance to date. Several projects embody the concepts of distributed generation (DG) and demand-side management (DSM) as well as utilization of renewable energy. These residential and commercial grid-connected PV systems have reduced electrical demand at each site during the Company's summer peak hour from 1986 through 1993. In addition, during many of the hours around noon the residential systems have provided all of the energy for neighboring homes without PV systems. Transmission and distribution losses associated with the normal supply of energy to these sites was therefore minimized during these hours. On-site production of electricity via photovoltaics may also result in significant environmental benefits, particularly in summer, through displacement of energy from fossil-fueled peaking units. Other types of projects discussed include (1) a solar monitoring network, with simulation of electrical output for three types of PV systems, (2) a unique PV-assisted DC lighting system for a commercial building, (3) a large (100 kW) ground-mounted PV system, (4) a combination solar-PV and solar-thermal system, and (5) development of a single-module inverter     

The New England electric photovoltaic systems research anddemonstration project

The design, installation, and operation of photovoltaic systems at 30 residences and 8 commercial or institutional sites are described. The correlation between hourly PV production and system daily load profile, the potential impact of PV production on residential customer load, the relationship between PV energy production and cloud cover, and the monthly variation in energy output are discussed     

Performance of grid-connected photovoltaic systems on residencesand commercial buildings in New England

The focus is a detailed examination of energy production, including a discussion of the capacity value of photovoltaic (PV) systems in New England. Data are presented on the customer demand reduction potential of roof-mounted residential PV systems. It is shown that these systems can contribute, on average, 63% of their normalized capacity (1.8 kW) during 6-h peak load periods. The range of output is 34% to 80% during these periods. Reverse energy flow (customer to utility) from residential PV systems has been analyzed. The data indicate nonzero reverse energy flow for almost all participants in summer, and high amounts (approximately 50%) for one group of participants. The commercial and institutional PV systems generally operate in a more hostile electrical environment. In consequence, they have required more attention to maintain operating status and metering accuracy     

Radio control of air conditioning in Rhode Island

A test is reported in which a VHF-FM radio communication system was used to control the compressors of central air-conditioning systems of 50 residential customers and 35 small commercial customers in Rhode Island between the hours of 12:00 and 5:00 pm during weekdays from June through September of 1988. Topics discussed include recruitment of participants, pre-experiment testing, equipment performance, and analysis of results. The hourly diversified demand reduction attributable to control was 1.0 to 1.6 kW per residence during control hours when the average outside temperature ranges from 88 to 95°F. Commercial units showed a relatively constant demand reduction, on the order of 2.5 kW, at all temperatures in excess of 80°F     

Radio control of water heaters in Rhode Island

A VHF-FM radio communication system was used to control the lower heating elements of 100 residential customers in Rhode Island. The hours of control were 1:00 to 5:00 p.m. during weekdays from June through September of 1987. Topics discussed include sample selection, pre-experiment testing, equipment performance and analysis of results. The diversified demand reduction attributable to control in the summer is less than anticipated, averaging 0.26 kW per residence during control hours