Adding Solar Power to a Typical Home
If you are a residential or business owner currently connected to the utility grid, a Grid-tied system is the most cost effective option to start offsetting your monthly power bill.This type of application can often be limited by space constraints or your electric company’s policies for installation. This popular, efficient, system converts the sun’s energy directly to standard AC power to be synchronized with the utility. Some systems can easily be added onto, should you decide to start small, building on as your budget allows.
The solar panels can be mounted on the roof or nearby on a ground mount. If you choose to install a roof mounted system, expect it to be a low profile installation of aluminum extrusions which hold the modules.These panels come stock with wires that plug together to make electrical circuits which will eventually lead to a disconnect at ground level. From there, the circuit goes through an inverter (which converts DC voltage from the panels to standard 240V AC). The output of the inverter is then connected to the electrical system of the home. This is most typically accomplished by adding a 240V circuit to the existing load center- your normal service panel. The inverter is able to sense the utility electricity and synchronize its output to it perfectly. In other words, the solar array’s energy is mixed together with the grid’s energy, offsetting your electric bill. If your solar array is producing more energy than you are using it will flow to the grid and will be shared with your neighbors. This is also known as “Net Metering”, if offered by your utility. It could potentially give you credit for each kWh at the retail price and your meter will spin backwards! (Be sure to check with your utility company regarding these details).
Grid-Tied Components (can be as simple as):
Mounting structure, unless building-integrated
Many utilities offer significant rebates to encourage solar electricity. In sunny areas, the production from the solar electric systems can help reduce peak loads in the summer. In Colorado, the largest utilities are required to offer a rebate. There is an additional payment available for a "Renewable Energy Credit", or REC, which allows the utility to count your solar generating system towards their total renewable generating capacity. Check out our local and federal incentives link on the left or click on the link below to check out our grid tied packages.
With this type of system, storing energy is normally not done. When the utility grid goes down (power outage) your system will also shut down. This is primarily to ensure the safety of electrical workers who may be working tirelessly to get the grid back up and running. One of the newer grid-tie inverters does have the ability to provide a small amount of 120V AC power even when the grid is down, as long as the sun is shining. This is the TL series from SMA.
There are several types of hybrid grid-tied systems (referred to as grid-tied with battery backup) that are popular for areas that suffer regular power outages. With these systems, when the grid (the utility) fails, the output of the system must be isolated from the grid for safety. Then, a battery bank takes over and provides energy to power lights, a refrigerator, security systems, or whatever you decide is the most important during a power outage. This allows the solar array to keep working even when the grid is down.
In greater detail, this type of system, unless very large, usually requires household loads to be separated into two groups with a subpanel: loads to be backed up by battery and loads that will only use grid power. Deciphering between these types of loads can be extremely important as some home electrical loads are not practically powered by batteries. The required equipment is similar to an off-grid system (please see remote system tab) although specific components will differ. A smaller, maintenance-free battery may be more appropriate, for example. Utility approval will still be required for this type of system if you want to sell power during times when the grid is functioning.
Should storing energy be an option you would like to consider (for those pesky power-outages) a grid-tied battery back-up system could be the best option for your home or business. Different types of systems are more optimized for more efficient selling, or better battery management. Please give us a call to discuss what type of system fits your desired outcome the best!
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