What does “PV” stand for?

PV is an acronym that stands for photovoltaic. The term photovoltaic represents the union of two words: photo, meaning light, and voltaic, meaning electricity produced by chemical action. Photovoltaic systems convert light energy, photons from the sun’s rays, into electricity through the photoelectric effect. When sunlight hits the PV panel, photons knock electrons into a higher state of energy, creating electricity.

How is power and energy measured from a PV system?

The capacity of a PV system is stated in terms of the number of watts, kilowatts or megawatts it produces in standard sunlight conditions (STC). For the northeastern United States, a good estimate is: For each kilowatt of PV capacity AC-installed, the system will produce approximately 1,000 to 1,300 kWh (kilowatt-hours) per year. For example, a 100 kW system will generate about 100,000 to 130,000 kWh per year.

How much roof space do I need for a PV system?

Most PV systems produce about 8 to 10 watts of power for each square foot of roof surface. A typical 100 kW system will require 8,000 to 10,000 square feet of unobstructed area.

What happens if PV panels are shaded?

Shade on PV panels decreases a system’s output. While some shading can be acceptable during certain times of the day (early morning and late afternoon), it is important to minimize the impact that shading from trees, nearby buildings, roof mechanicals and other factors can have.

How long do PV systems last?

If a PV system is designed, installed and maintained well, it will operate for as many as 40 years. All solar modules utilized by SES carry a 25-year warranty.


What happens if my system produces more electricity than I need?

In many states, including New York, New Jersey and Connecticut, utility customers can take advantage of a policy called net metering. Net metering allows all unused power generated by your PV system to flow back into the electric grid, for the benefit of others in your community. Your utility company will purchase/credit your excess solar electricity at retail rates, directly offsetting costs that are incurred during times when consumption is higher than the PV system's production.


Will a PV system save me money?

A solar PV system is a long-term investment that is guaranteed to pay dividends. On-site power generation reduces the amount of billable energy you will consume from the utility grid, thereby leading to appreciable savings on energy costs. In addition to the money saved on energy bills, policies like net-metering allow PV system owners to profit from their system’s excess generation. Moreover, a solar system will allow you to lock in a price per kWh thereby protecting you from rising future energy costs. Additionally, a PV system adds value to your property and will confirm a company’s “green” commitment, ensuring new customers and attracting employees. 


How am I going to pay for my PV system?

A cash purchase may be the best option for companies with capital to spend, and that are eligible to take advantage of available tax benefits.

Lease agreements may be preferable for capital or tax-credit constrained companies that plan to eventually purchase or own a system.

A power purchase agreement, or PPA, is a long-term contract to buy solar energy. Solar PPAs are agreements between a provider and a customer for the sale and purchase of solar energy at a long-term rate, sometimes equal to or less than current utility rates. Under this scenario SES will install and maintain your solar project. As the customer and host site, you pay only for solar energy as it is generated with no up-front expenditure for the equipment.


What are the components of a PV system?

A complete solar electric system is made up of several building blocks. First, there are solar cells. Cells are manufactured from semiconductor materials such as silicon, sometimes boron and phosphorous, wired together to form a solar module. Modules (or “panels”) are wired together in series and parallel to form the array. PV systems produce direct current (DC) electricity. In order for a PV system to produce electricity that a typical business can use, the DC electricity must be converted to alternating current (AC) electricity. The inverter converts DC electricity to AC electricity. The design and size of the PV system determines whether there will be a single large inverter or several smaller inverters. The balance of system (BOS) includes racking, fasteners, switchgear, junction boxes, inverters, conduit, grounding equipment, meters, the Data Acquisition System (DAS), etc.

What size PV system will I need?

The size of your system depends largely on how much electricity you are currently consuming. The less energy you use the smaller the system you may need.

Do PV systems store energy?

All of the PV systems engineered and maintained by SES are “grid-tied,” and as such do not store electricity. The grid therefore provides power when the PV system is not generating. The grid accepts all excess energy production during times when the PV system is producing more than is being consumed on site. The most common way to store energy from an “off-grid” PV system is in a battery. While battery storage allows a customer to be independent from the grid, batteries also add to the expense of the system, may be large, require special handling, and can emit toxic gases.


Do I need to install a new roof before installing a rooftop PV system?

As part of our site assessment and design process, SES will assess the condition of your roof and recommend any necessary repairs or replacement. Your roof needs to be in good condition prior to installation. Once installed, solar panels can reduce the UV "wear and tear" on your roof, but it is important to begin the project with a good solid roof.


What kind of maintenance will my PV system require?

PV systems require very little maintenance. Rain will typically be sufficient to clean the modules. But on occasion they may need to be washed, and debris (e.g., leaves) will need to be removed. SES standard maintenance contract includes any cleaning, ballast inspection, label inspection, inverter inspection and checking for module and rack degradation. By means of a Web-based Data Acquisition System (DAS), SES will track and verify system performance relative to weather adjusted projections. 


What incentives are available to reduce the cost of a PV system?

Photovoltaic (PV) systems are eligible for a range of cost-reducing local, state and federal rebate, incentive, loan, grant, lease, and tax incentive programs. The federal investment tax credit (ITC) is available for 30% of the cost of a photovoltaic system and is now available as cash as soon as your system has been installed and passed all inspections. 


What is an average break-even point for a PV system?

The break-even point, or payback period, for a PV system generally depends on financing and incentives, but on average in the Tri-State areas business can expect to see a 100% return of capital within four to seven years.