Frequently Asked Questions

Below you can find a list with some of the more frequently asked questions. If you have any other questions, please call or email us through our Contact page.

What are the benefits of using PV solar systems?
Home or business owners are able to generate electricity from sunlight. This solar generated energy is used to offset or replace power that would normally be purchased from the utility. There is no fuel cost for the energy you produce, no waste and no pollution as well.
What is Net-Metering?
For owners of PV systems, net metering provides an opportunity to sell excess electricity produced to your local utility company. In the U.S.A. most of the states currently have net metering policies in place. Net metering means that the amount of solar electricity produced (measured in KWh) is subtracted from your overall usage, meaning you only pay the utility for the difference (the “net” amount).
What is a grid-tied solar system?
98% of PV solar panels installed in the USA are grid-tied systems, meaning that the system is tied to the power grid (local electric power utility company). The solar power is added to the grid power, reducing the amount of power that must be purchased from the utility.
What is an off-grid solar system?
An off-grid solar energy system is where there is no connection to the utility company power grid. This type of installation requires a charge-controller, a bank of batteries and in most cases an inverter, so that electric power requirements can be met at night or during cloudy conditions.
What is a battery back-up PV system?
This is where you have a battery system that remains charged by the PV panels. When the power grid goes down, the batteries supply power to designated critical loads in the house. When the grid reconnects, the power from the PV array goes on to the grid allowing for net metering.
What are the different types of PV panels?
There are currently four main types of solar PV panels:

Monocrystalline – these are made from cells created by cutting thin slices from single crystal silicon block and are higher in efficiency, but also higher in cost per watt. They are easy to spot because they have a smooth even color, usually black.
Polycrystalline – these are made from cells created by cutting thin slices from polycrystalline silicon block and are slightly lower in efficiency, but also lower in cost per watt. Polycrystalline silicon is made by combining many individual crystals. They are easy to spot because they have an uneven crystallized look, usually blue.
Multicrystalline – another term for polycrystalline.
Thin film – these are made by depositing a thin layer of very fine silicon (amorphous silicon) or other photovoltaic material, on a substrate. These are much lower in efficiency that crystalline cells, and somewhat cheaper per watt. Their low efficiency makes them undesirable for residential applications because they consume a large amount of roof space compared to mono or poly panels.

How do I decide how large my PV solar system should be?
Another benefit of PV systems is that they can be almost any size and still have a good return on investment.
How much power will a solar PV system produce?
For an ideal installation in the Denver metro area, a 3000 watt system will provide about 4,600 kWh per year.
How much power will a solar PV system produce?
One of the leading causes of power loss in a solar PV system is when part of the panel or array becomes shaded. A solar installation should be designed in a way such that none of the panels are even partly shaded at any point of the day.
How much roof space does a PV system need?
Approximately 10watts of modules per square foot, a typical 3000 watt system needs about 300 square feet. Depending on installation factors, the required square footage of roof space will be somewhat larger than simply the area of the panels.
Do solar panels have to be installed on the roof?
Solar panels can be installed on the roof, on the side of a building, on the ground or on a pole. The most cost effective installation will usually be on a roof, but if roof or shading conditions prevent the use of the roof we can help you review other options.
Do installed solar panels have to face a southerly direction?
For best production, yes. Any time sunlight hits the modules, they produce electricity.
What about cloudy days?
PV solar panels will generally produce electricity though at a much lower rate.
How long will a solar panel system last?
Solar panels are known to last 40 years or longer. Typical guarantees of a solar panel include five years workmanship and materials warranty and a 20-25 year performance warranty. The typical PV panel performance warranty will guarantee 90% of rated production for 10-15 years, and 80% for 20-25 years. Solar panels are designed to withstand hail, severe wind and weather conditions assuming proper installation.
How do I know if a solar PV system is a good choice for me?
Most everyone can benefit from using solar energy. The real choice is where do you wish to purchase your energy from?
What are the maintenance requirements or other costs for a PV system?
For a grid-tied system where no batteries need be replaced, there is typically little or no maintenance required. You might consider a periodic inspection to ensure that the panels remain clear of leaves, dirt, bird droppings etc. Unless there is an equipment failure there should be no maintenance required.
Besides the solar panels, what else is needed for a complete system?
In a grid-tied system, local power company regulations must be met, each are is different. Otherwise, the system will include the panels, mounting hardware, connecting wires, and an inverter to convert the DC power from the panels into the correct AC voltage.
What are solar inverters?
An inverter is any device that inverts DC (direct current) into AC (alternating current). In a solar installation, an inverter is a centralized device that connects to and manages the performance of the solar panel array; it aggregates the DC power coming from the panels or strings of panels and inverts the DC power into single phase (or three phase) AC power at the correct voltage for delivery into the users electrical system, and provides equipment protection and safety features. The better inverters on the market also allow for data logging and web-based remote monitoring of important performance metrics and power generation.
What are micro-inverters?
In a solar application, a micro-inverter is a small de-centralized inverter that attaches directly to each panel. The advantages of micro-inverters are several; they may be safer for the installer because they eliminate high voltage DC in the system and instead use household type power; installation may be quicker, and, performance of the panels or strings can be improved if there are shading conditions or otherwise poorly performing panels within the array.
Little is known about the longevity of micro-inverters as they are a new product without an extensive track record. Further, a failed micro-inverter may be very hard to access and replace if it is in the center of a multi-panel installation.
At some point it is possible that micro-inverter technology will reach a point where DYI solar installations may become possible. For now, only a licensed electrician can commission a grid-tied system regardless of the type inverter used.
Will my solar PV system include batteries?
In a grid-tied system you do not need batteries. When the grid goes down, your solar systems disconnects from the grid and you still will not have power. If you wish to have power when the grid goes down, you will need batteries.
Can I power my entire building with solar panels and disconnect from the utility company?
Yes you can. In an off-grid installation, you must have batteries, a charge controller and an inverter – in some cases the batteries will cost nearly as much as the solar panels and only last 8-10 years before replacement becomes necessary. Off-grid solar is achievable, but is very costly and only recommended for locations where there is no grid to connect to.
What happens if the solar panels are covered by snow?
Some sunlight will penetrate the snow, causing the panels to warm and eventually melt the snow. Spraying the panels with water from a garden hose can speed things along. On a single story roof, a snow rake can be the best option to remove most of the snow allowing the panel to melt the remainder quickly, we suggest using a model with a rubber squeegee blade attached to the end of it. We do not recommend homeowners climb on to a roof.
How do the solar panels stand up to hail, wind, hurricanes etc?
Solar panels themselves are built using tempered glass for durability and safety and are designed to withstand 1″ hail (perpendicular to the glass) and high winds. Depending on the wind-load requirements in your area, heavier mounting hardware may be required.
Will solar panels damage my roof?
Properly installed solar panels will not damage your roof. If your roof is near the end of its expected life, it might be a good idea to consider replacing the roof before adding solar panels, because removing and reinstalling the panels can add to the cost of a roof replacement.
How long does it take to install a PV system?
A typical residential roof installation can be completed in 2-4 days. The number of panels and type of installation will affect the installation process.
Is a building permit required to install a PV system?
A professional installation will nearly always require a permit. A call to your local city government (electrical inspector) would clear this up.
What does a solar PV system cost?
If you know your electrical costs, then with rebates and government credits, often less than 10 year simple payback. Without rebates between 15 and 20 years. Even though this seems long, you are purchasing 40 years or more of electricity up front.
Does a solar PV system affect the resale value of my property?
Yes it does. Available real estate property resale value data indicates that money spent on solar panel installations is recoverable and may actually increase the value of the home beyond the amount spent. Recent data indicates that home with PV systems sell sooner than those without systems.
How do I qualify for and take advantage of state and federal subsidies, rebates or incentives for solar power?
Each individual situation is different and it is suggested that you consult with a tax professional. More information is available here http://dsireusa.org/
I rent my building - does it make sense to install a solar power system
For tenants interested in a solar installation, some discussion and agreement with the building owner will be required. In general it is also beneficial to the owner, particularly if it does not require any payment on his part.
I live in a condo - will I be allowed to install a solar panel system?
This will depend on the condo association rules. You must discuss this with your association.
How fast are PV efficiencies improving?
Efficiencies are improving but not quickly. Higher efficient modules cost more than lower efficient modules. What you want to look for is long term quality of the products and installation at a low price. The bottom line is that the fuel is FREE. Efficiency does not actually matter. Only in limited fuel products does efficiency matter.
Should I wait for the next better technology?
Currently a PV module has no moving parts is warranted for 25 years will last more than 40 years (maybe 100 years) the materials are abundant, readily available here in the U.S. and 95% recyclable. There have not been many products every manufactured that can compare with these modules. You can wait for better technology, but it may never arrive.