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The Manager of Engineering, Planning, and Energy Management in the Cornell Utilities Department (position currently held by Lanny Joyce) and the Kyoto Task Team will be involved in project selection and funds allocation.
The money in this fund will not be used to pay the entirety of any project but rather to subsidize the cost until it is at a level at which the University is comfortable investing. This ensures that the University has a stake in each of the projects and has incentive to publicize and maintain the system. It also will allow the funds to make more PV projects possible.
Future projects will be determined by the amount of money available in the fund with preference given to projects with the highest visibility.
How Much It Will Cost:
How much power will PV make in Ithaca?
Photovoltaic systems are described by their peak power output. This is the amount of power that they would generate under full sun conditions. A 1kW PV system would produce 1 kWh during one hour of full sunlight. However, we do not have full sunlight all day or all year round. In the winter the sun is weaker than the summer and when it is cloudy the PV only makes a fraction of its rated power.
A 1kW PV array will produce approximately 1,600kWh AC per year in Ithaca on an average, south-facing sloped roof. This takes average efficiency losses into account.
How much is this power worth?
The utility is required to net meter PV systems under 10kW. In a net metering arrangement, when the PV array produces more power than the building is using, the extra energy is fed onto the grid to power neighboring buildings. When this happens, the electric meter actually spins backwards. When the building is using more power than the PV array is producing, the grid makes up the difference and the meter spins backwards. The electric bill is the net energy use -- what was taken from the grid minus what was put back onto the grid. In this arrangement, every kWh produced by the PV array is worth the retail price of electricity because it displaces the retail electricity being purchased. Electric retail rates in the Ithaca area are about 12 cents/kWh, Cornell rates are slightly lower.
If the system is over 10kW it cannot be net metered. Any excess power that is not used by the building is still fed onto the grid, but the meter does not spin backwards. Instead a second meter is installed to count the energy put back onto the grid and the utility then pays the wholesale rate for this energy, just like any other power plant. The wholesale rate is only about 3 cents/kWh. A system of this size only makes sense if the building will always use as much energy as the PV system is producing. In this scenario, no power is sold back to the grid and all of it is used to displace energy that would have been bought from the grid, effectively still paying the 12 cents/kWh.
Electricity demand in the Ithaca area is highest in the middle of hot summer days, exactly when PV is producing the most amount of power. This is the time when the most expensive, dirtiest power plants are used to provide for the high demand. PV not only cuts the amount of power needed from those dirty power plants, but it also lowers the cost of electricity by shaving the peak demand. Though the local Utility does not use demand pricing but it is possible it could switch to this sytem in the future like many other utilities. In demand pricing, a customer pays more for electricity when demand is high and the more expensive plants are used. If the local utility were to implement demand pricing in the future, the PV systems would save the University much more money.
How much does PV cost?
The New York State Energy Research and Development Authority (NYSERDA) lists $6,373 - $12,604 as the range of costs per installed kW of the approximately 150 systems to which it had given incentives from 2001-2003, with $8,200 being the average.
To help bring this price down, NYSERDA offers rebates of $4,000/kW installed PV, bringing the average price down to an average of $4,200 per kW installed. If things are done carefully with respect to cost, it could be as low as $2,500 per kW installed.
How long will it take to pay for itself?
At the average cost, it would take about twenty years for the PV system to pay for itself through electricity savings if put on an off-campus building. With the lower-end cost it would take about twelve years. If the owning department were to pay the equivalent of seven years of electricity savings, that would account for $1,400/kW. The Solar Fund would pay the remaining amount.
Is it important that the system pay for itself? Let me ask a different question: What was the payback on the retuning of the bells in McGraw tower five years ago? Was it worth doing anyway? What was the payback on the fancy cantilevered room on the side of Duffield Hall? Did the University think it was worth doing anyway?
As Steven Strong, president of Solar Design Associates, said when he gave a lecture at Cornell three years ago, it would almost be easier to convince people to buy PV if it didn't produce any electricity. If it didn't produce anything of monetary value but could simply be evaluated on a feeling, we would see it at least as often as we see marble facades. If interested in this topic, please read an opinion column on the subject that was published in the Cornell Daily Sun in September 2003.
