Solar Electric - essential information
We are grateful that there is so much interest, but we continue to be overwhelmed with inquiries. So...
First... study the information below to
help you determine whether a solar electric (aka PV, photovoltaic) system will
work for you. We've worked very hard to compile and keep this information
as up-to-date as possible. Please read it.
Second... after reading and understanding this webpage, fill out our secure CLIENT INFORMATION FORM for PV systems. This gives us some basic information to begin to address your situation and serve you well. We appreciate your understanding and assistance. Thank you!
Here's a listing of quick links to the various topics discussed below.
Energy efficiency
- Get an Energy Audit to identify your building's greatest inefficiencies. This NYSERDA webpage lists certified Building Performance inspectors. Look for someone who will assess not only your heating system and cold air infiltration, but will also evaluate the energy use of appliances, lighting, and other "plug loads" in your home.
- Insulate everything - extremely well - particularly roof, walls, basement, rim joists, hot water tanks and hot water pipes. Repeat - insulation everything! Boring - yes - but way more cost-effective than buying renewable energy to meet conventional (=wasteful) energy usage.
- Find where drafts enter (air infiltration) and apply non-toxic sealants to eliminate them.
- Replace ancient incandescent bulbs with compact fluorescent lights (CFL's) or light emitting diode (LED) lighting.
- Replace electric heating systems with more cost-effective options.
- Replace single-pane windows with double- or triple-pane glazing.
- Replace old, inefficient appliances, especially refrigerators and freezers, with efficient ones. Most appliances manufactured in the 20th century "oil age" will be inefficient and unbecoming of a 21st century "solar age" household. An "EnergyStar" rating is not enough - read, compare and understand the actual energy consumption of each model available.
- Replace electric hot water heaters with solar thermal systems backed up by natural gas (NG) or propane (LP) water heaters, preferably the tankless or instantaneous (on-demand) type.
- When submersible well pumps need replacement, use low surge or "soft start" models such as the Grundfos SQ or SQE.
Renewable energy systems will be most cost effective in buildings that are already energy efficient. Efficiency measures are absolutely the best investment you can make in terms of energy costs. Here's a short list of things you can do...
Site requirements
- a relatively large roof area (about 70 sq.ft. of space per kW) without obstructions (vents, chimneys, protruding dormers, etc.);
- no shading year-round between the hours of 9am and 3pm from trees, other buildings and common obstructions such as vents, chimneys, dormers, etc.; and
- a relatively south-facing roof orientation (+/- 30° of geographic south is acceptable). If your roof cannot provide this, you may wish to consider a ground-mounted system - which provides much more flexibility in locating the modules as well as greater year-round energy production.
For a roof-mounted PV system, your site will require:
Although a true south (geographic not magnetic) facing system is optimal, a SE or SW module orientation results only in about 15% energy loss. Conventional wisdom was that a direct east or west PV installation would see an efficiency loss of at least 30% - however, if the slope of an east or west facing roof is 4:12 (about 18 degrees from horizontal) or shallower, the efficiency loss can still be less than 20% relative to true south. NYSERDA provides their full PV incentive (see Financial incentives and tax credits below) for systems with less than 20% energy loss due to shading or orientation. However, NYSERDA will still provide an incentive (albeit reduced) for systems with more than 20% energy loss relative to an unshaded, south facing solar array.
A distinct benefit to pole-mounted systems is that you can change the tilt angle seasonally to increase efficiency and brush off snow from the modules in winter. However, these systems are more expensive due to the substantial foundations required to secure the poles as well as the excavation for electrical conduit extending from the pole site(s) to a building.
Figuring electric usage
We size solar electric systems based on your electric usage, designing them to produce all or some fraction of actual usage. In order to receive the NYSERDA incentive, a PV system cannot be sized to produce more than 110% of "demonstrated usage" - which is usually documented by past electric bills.
You can find your annual electric usage in kilowatt-hours (kWh) either on your utility bill, via the utility company's website, or by calling the utility to request this information. You (and we) will use this information to determine what size of system will meet your needs. Let us know if you anticipate your usage to be significantly decreasing (for example, through efficiency measures such as those listed above) or increasing for some reason (for example, more people in your household).
Do not be disheartened by the current level of your energy usage and the cost of the PV system (see next section) needed to produce all of this electricity. Refer to the energy efficiency measures above, and keep in mind that you would be taking positive action by installing a system that may meet only 1/2 or 1/4 of current usage. We have found that, over time, PV system owners gain an appreciation not only for the output of their system, but also for their electric usage habits - electric consumption almost always decreases. Also note that PV systems are inherently modular - they can be added to later on. It will be most cost-effective to let us know of this possibility early in the design phase so that we size wires, conduits, and other balance-of-system components accordingly.
For new residential construction, please refer to the New homes section below.
System size, production, and pricing
These are very rough ballpark estimates for grid-connected, battery-less solar electric systems using high-efficiency SunPower solar modules - which is what we design most often and what most people choose. There is a rough economy-of-scale as system size increases. Detailed costs will be presented after a Site Evaluation and specific design(s) have been worked out for your site.
| System size |
Annual kWh |
Mount style |
Total Cost |
NYSERDA incentive |
NYS* tax credit |
Fed** tax credit |
Total incentives |
Final cost |
| 1 kW | 1,110 | Roof | $12,000 | -$4,000 | -$2,000 | -$2,000 | -$8,000 | $4,000 |
| Pole | $14,000 | -$4,000 | -$2,500 | -$2,000 | -$8,500 | $5,500 | ||
| 2 kW | 2,219 | Roof | $24,000 | -$8,000 | -$4,000 | -$2,000 | -$14,000 | $10,000 |
| Pole | $28,000 | -$8,000 | -$5,000 | -$2,000 | -$15,000 | $13,000 | ||
| 3 kW | 3,329 | Roof | $33,000 | -$12,000 | -$5000 | -$2000 | -$19,000 | $14,000 |
| Pole | $39,000 | -$12,000 | -$5000 | -$2000 | -$19,000 | $20,000 | ||
| 4 kW | 4,438 | Roof | $40,000 | -$16,000 | -$5000 | -$2000 | -$23,000 | $17,000 |
| Pole | $48,000 | -$16,000 | -$5000 | -$2000 | -$23,000 | $25,000 | ||
| 5 kW | 5,548 | Roof | $50,000 | -$20,000 | -$5000 | -$2000 | -$27,000 | $23,000 |
| Pole | $60,000 | -$20,000 | -$5000 | -$2000 | -$27,000 | $33,000 | ||
| 6 kW | 6,658 | Roof | $57,000 | -$23,000 | -$5000 | -$2000 | -$30,000 | $27,000 |
| Pole | $69,000 | -$23,000 | -$5000 | -$2000 | -$30,000 | $39,000 | ||
| 7 kW | 7,767 | Roof | $66,500 | -$26,000 | -$5000 | -$2000 | -$33,000 | $33,500 |
| Pole | $80,500 | -$26,000 | -$5000 | -$2000 | -$33,000 | $47,500 | ||
| 8 kW | 8,877 | Roof | $72,000 | -$29,000 | -$5000 | -$2000 | -$36,000 | $36,000 |
| Pole | $88,000 | -$29,000 | -$5000 | -$2000 | -$36,000 | $52,000 | ||
| 9 kW | 9,986 | Roof | $81,000 | -$32,000 | -$5000 | -$2000 | -$39,000 | $42,000 |
| Pole | $99,000 | -$32,000 | -$5000 | -$2000 | -$39,000 | $60,000 | ||
| 10 kW | 11,096 | Roof | $85,000 | -$35,000 | -$5000 | -$2000 | -$42,000 | $43,000 |
| Pole | $105,000 | -$35,000 | -$5000 | -$2000 | -$42,000 | $63,000 | ||
| * Applicable only to primary residence in NY. Tax credit is an estimated amount dependent on taxes owed. | ||||||||
| ** Tax credit is an estimated amount dependent on taxes owed. | ||||||||
| The electric production figures in this table are based on (1) a daily average of 3.8 hours of "full sun" (1000 W/m2) annually for Ithaca NY, (2) an overall efficiency factor of 80% (0.8) to account for energy losses in the system, and (3) an unshaded, south facing solar array oriented approximately 35 degree from the horizontal - for example, an 8:12 roof pitch. | ||||||||
Grid-connected systems and net metering
Grid-connected or grid-tied solar electric systems are just that - your PV array is connected to the utility, sending its electric production to the grid during periods of excess generation (mostly sunny days) and taking electric from the grid during periods when household usage exceeds generation (at night and on very cloudy days).
In New York, starting Jan 1, 2009, residential installations of up to 25kW AC output are eligible by law for net metering (the limit is 10kW until 1-1-09). With net metering, the utility company must credit excess PV production (mostly sunny days) towards future electric use (nights, cloudy days) at the full retail electric rate.
Your monthly billing will reflect your net usage - a credit if you produce more electric than you use, or a charge equal to your usage minus your production. At the end of one year, any remaining (unused) credit is paid to the system owner at the wholesale or "avoided cost" electric rate. In essence, with net metering you are using the utility system as an electric storage system. However, under current regulations, it does not pay to generate a great deal more electricity than your household will use annually because the excess is paid to you at the prevailing wholesale electric rate.
Grid-connected systems with battery backup
If you want backup power in the event of a utility failure, you'll need batteries to store some fixed amount of the solar energy. In this situation, we typically install a "protected loads panel" to service critical loads - such as electric power to heating system controls, emergency lighting, a well pump, and (possibly, depending on battery capacity) larger devices such as a refrigerator, etc. When the grid is functioning, these items will be powered by the grid; when the grid is down, your batteries will service these loads.
The system is set up so the battery bank is automatically monitored and kept fully charged, and all excess solar electric produced is sold back (net metered) to the utility when the grid is functioning. As in a battery-less, net-metered, grid-connected system, you will be credited at the retail rate for this excess production in a residential situation. It doesn't take much electric to keep the batteries full since you aren't typically drawing from them. Should the grid go down, you have full batteries ready to power your "protected loads" and recharge whenever sunlight is available.
In this way, one can minimize the expense of an otherwise very costly battery system necessary to power an entire house as an off-grid system. Even so, the battery backup system components will add a minimum of about 30% to the cost of a battery-less grid-tied system and utilize about 10-15% of its energy output to maintain batteries in a ready-to-go, fully-charged state.
Off-grid systems and batteries
If you are so far from the nearest utility pole that grid-connection is economically prohibitive, or you simply do not want to be grid-connected, you will need to produce and store (almost) all of your anticipated electric needs in batteries. Be aware that batteries are the most short-lived component of a PV system, with a typical useful life of 2 to 10 years (yes, that's a big range!) depending on how they are used and maintained.
If you are considering this type of system, recognize that this is a serious choice which, in most circumstances, involves making changes in personal energy use habits and becoming aware of when solar energy is available and when it is not. For "off-gridders", it is critically important to be as energy efficient as possible to keep system costs within reason. We strongly encourage you to build a super-insulated house, well beyond the current building code requirements, and to incorporate passive solar into building design wherever possible.
Please see our list of off-grid recommendations for specific off-grid home and appliance recommendations. Investing in the most energy-efficient appliances, such as refrigerators, clothes washers, lighting (CFL's and LED's) and other such measures will be far less expensive than installing a larger PV system and battery bank. Check out the appliances carried by Backwoods Solar and Lehman's.
Off-grid PV system owners often consider investing in a backup electric generator to charge batteries during periods of low solar generation. A less-noisy, less-polluting solution, if you have reasonably good wind speed at your location, is to install a small wind turbine to provide electric during our sun-deprived winter months when the wind is strongest.
To properly design an off-grid system, we'll need a clear idea of how much electricity you will need. You must make a list of what electrical items you anticipate using, find the number of watts or amps the item uses, and estimate how much time, on average, you will use the item daily or weekly. With that information, we can come up with an estimated system size and an idea of system cost. This may seem tedious, but underestimating your actual electric usage can leave you in the dark, and oversizing the system will incur unneeded expense.
Off-grid PV systems are not eligible for the NYSERDA incentive or for the NYS income tax credit. They appear to be eligible, however, for a Federal income tax credit of 30% (capped at $2,000). Such systems can make financial sense if you are a significant distance from the nearest utility pole. If you simply want the security of having (some) electric when the utility is down, please refer to the preceding section on grid-connected systems with battery backup.
Since lead-acid batteries are becoming quite expensive due to recent large increases in the price of lead, proper selection and sizing of a battery bank is crucial. For technically-inclined persons, our battery bank sizing webpage provides some recommendations for matching a battery bank to the size of a PV system.
New homes
- Based on what you want to spend on the system.
- Based on your current usage. For this, we'll need to know your average annual electric usage in kilowatt-hours (kWh) - please see figuring electric usage. If your new home will have significantly different features, such as moving from electric baseboard heat to a gas boiler, this method will be far from accurate.
- Based on the number of people who will be living in the home. Very roughly, this works out to between 5 and 10 kWh per day per person (regardless of age). This is quite a broad range, so is a very general guideline.
- Based on a quantitative estimate. The most accurate estimate requires that you make a list of electrical items you anticipate using and estimate how much time, on average, you will use each item daily or weekly. Although this is an involved exercise, it will quickly help you realize why choosing energy-efficient appliances makes sense.
We can give you much more specific information after a Site Evaluation or Project Consultation meeting. It's a good idea to have us review your home design ideas before building plans are finalized so we can offer recommendations about the benefits, requirements, and limitations of renewable energy systems.
That said, we strongly encourage you to build a super-insulated house - well beyond the building code requirements - and incorporate passive solar into your design. Also, seriously review our off-grid recommendations webpage called What You Can and Cannot Do and consider investing in the most energy efficient appliances.
For new homes that meet NYSERDA's EnergyStar building criteria, there is a slightly higher PV incentive level - an extra $0.50 per DC watt ($500 per kW). So, to find the ballpark system cost, subtract an additional $500 per kW from the Final Cost figures in the cost estimate table above.
To properly design a system for a new home, we'll need to develop an estimate of the appropriate system size. We can do so in several ways:
Financial incentives and tax credits
- The PV system must be grid-connected.
- The utility company must pay into the System Benefits Charge (SBC). To see whether your utility company participates in this program, please refer to this NYS Department of Public Service webpage. To our knowledge, all NYS investor-owned utilities, including NYSEG and National Grid, participate in this program.
- The proposed system must be designed to generate no more than 110% of "demonstrated" or anticipated electric usage.
- A residential system cannot receive incentives for any capacity over 10kW (DC rating).
- A non-residential system cannot receive incentives for any capacity over 50kW (DC rating) per utility meter and/or physical site and no single non-residential customer may receive incentives for any capacity over 100kW.
NYSERDA PV incentive program
NYSERDA (New York State Energy Research and Development Authority) offers its PV incentive program (PON-1050) to help offset the cost of solar electric systems. For residential PV systems, NYSERDA provides $4 per watt ($4,000 per kW) up to 5kW and $3 per watt ($3,000 per kW) for each additional kW from 5kW to 10kW.
For commercial or municipal systems, NYSERDA provides $4 per watt ($4,000 per kW) up to 25kW and $3 per watt ($3,000 per kW) for each additional kW up to 50kW.
EnergyStar projects and building-integrated PV (BIPV) are eligible for an additional $0.50/watt ($500 per kW). To qualify as an EnergyStar project, the contractor or owner-builder must register the project through NYSERDA. Here is NYSERDA's definition of BIPV:
A building-integrated photovoltaic (BIPV) system generates electricity while also serving as an integral building component. To be considered building-integrated, a system must obviate the need for a conventional building material (e.g., asphalt shingles) and cannot merely apply energy generating capability to another building component at the site.
Please note that NYSERDA offers its this incentive program subject to the following restrictions:
New York state tax credits
New York State offers a tax credit of 25% of the system cost (after incentives are applied), capped at $5,000. This is only for grid-connected, primary residences. Here is a link to NYS tax form IT-255.
New York state property tax exemption
The original law exempting solar, wind and farm waste energy systems from NYS property tax for a period of 15-years, and which expired on January 1, 2006, has been reinstated and now extends through December 31, 2010.
To claim the exemption, the property owner must submit form RP-487 from the NYS Office of Real Property Services (ORPS) to the city or town assessor.
Federal tax credits
The Federal government offers a tax credit of 30% (after incentives are applied) for residential systems, capped at $2,000. To claim the credit or for more detailed information, refer to Federal tax form 5695.
The Federal Business Energy Tax Credit of 30% (after incentives are applied) has no cap. To claim the credit or for more detailed information, refer to Federal tax form 3468.
Financing
Once again (after a lapse of several months), NYSERDA is offering the Energy$mart Loan program to help finance solar electric systems.
Through participating financial institutions (banks and credit unions), this program provides interest rate reductions of 4% for up to 10 years with a $20,000 maximum for qualifying energy saving investments.
SunPower offers its own solar financing program for purchases of systems designed and installed by its dealers.
Payment schedule
- Scheduling Balance - approximately 10% of the total Purchase Agreement price - due when the contract is signed and returned to us;
- Materials Balance - approximately 65% of the total Purchase Agreement price - due before we can order materials the project;
- Completion Balance - approximately 15% of the total Purchase Agreement price - due on physical completion of the system (but not formal interconnection to the utility grid);
- Interconnection Balance - approximately 10% of the total Purchase Agreement price - due on formal utility approval for full-time interconnection of the system to the grid.
When we quote a system price before incentives, that is the total amount we need to receive to cover our costs and make a small profit. The NYSERDA incentive payments are, in fact, rebates refunded through a NYSERDA-eligible installer to the customer after the purchase is made.
A Purchase Agreement from Renovus specifies four (4) payments due from the Customer at various times in the "process" of design, installation and commissioning of a grid-connected PV system:
On the receiving side, the first 75% of the NYSERDA incentive is usually received by us about 4 to 5 weeks after all materials have been delivered to us for the project. The final 25% payment is received by us only after the system is completed, interconnected to and approved by the utility. With good timing, there can be some overlap of the receipt of the first incentive payment (75%) and the last two Balances due - but we can't guarantee this since it doesn't always happen. The state and federal income tax credits are applied to your taxes filed after the system has been commissioned. So, due to potential time lags in processing NYSERDA incentive payments, customers should be prepared to cover the entire cost of the system before receiving any rebate funds back from NYSERDA.
Where we install
Currently, we install throughout New York State, except for New York City and its immediately surrounding counties, and Long Island. For NYSERDA-eligible installers serving these locations, please consult this NYSERDA webpage.
What components we use
Renovus Energy is a design-build firm - we generate a design and choose components specifically tailored to your situation, and then install the entire project by our own experienced staff - subcontractors are rarely involved.
We use excellent quality components which we have field tested. We are particularly impressed by SunPower solar modules, the most efficient modules available to the residential solar market. As a Premier Dealer for SunPower, we have a guaranteed supply of these modules and matched inverters. SunPower solar modules also have an industry-leading warranty.
Our track record
Renovus Energy was formally incorporated in 2003, prior to which company founder and principal system designer Art Weaver had designed and installed off-grid PV and small wind systems for two years. All of our staff members bring unique qualities, experience, and commitment to our business. We do nothing else but install renewable energy systems full time and are experienced with all aspects of PV. Our work is highest Quality and we stand behind it. Period.
If you go to this NYSERDA webpage and click on the tab "Systems by Location", you'll see that the immediate Ithaca area has more NYSERDA-financed PV installations than anywhere else in the state. Renovus is responsible for a large fraction of those installations.
Site Evaluations
In order to design a residential PV system, our system designers will come to your site to evaluate its solar energy potential, system requirements and design possibilities. The fee for this visit, which will be refunded in entirety if you have us design and install a system, is $250 plus $1 per mile one-way travel beyond a 30-mile radius from Ithaca.
This visit will result in a formal Customer Purchase Agreement (CPA) and complete system design with a listing of materials, datasheets, itemized costs, anticipated incentive payments and estimated tax credits. Please note that, due to the complexity of what we call "the process," it usually takes at least five months from Site Evaluation to completed, grid-connected system.
Commercial systems
NYSERDA provides $4 per watt ($4000 per kW) up to 25kW and $3 per watt ($3000 per kW) from 25kW to 50kW for non-residential PV installations connected to participating utilities. Systems are limited to 50kW per customer meter and/or physical site and to 100kW per non-residential customer.
For commercial systems, there is also a Federal Business Energy Tax Credit of 30% with no cap. This credit applies to the cost of the system after any incentives (such as NYSERDA or government grants) are applied. For much more detail, consult the Database of State Incentives for Renewable Energy (DSIRE) website, here and here.
Net metering will become available for non-residential systems up to 2MW (yes, that's megawatts!) starting Jan 1, 2009. Until the recent extension of net metering to commercial systems, businesses needed to negotiate terms with the utility company and were generally offered only the wholesale or "avoided cost" price for excess electricity produced (this minimum was enforced by federal law).
Our fee for a commercial Site Evaluation is $500 plus $1 per mile one-way travel outside of a 30-mile radius around Ithaca. However, for small businesses with relatively simple electrical needs, our Site Evaluation fee will remain $250 plus mileage. Please note that (in either case) we will credit the entire fee back to you with your first payment if you choose have Renovus design and install your system. This visit will result in a complete system design and formal proposal with a materials list and itemization of all costs and incentive payments.