Grid-tied Solar with Net Metering
From a components and wiring perspective, grid-tied solar is the simplest way to gather and store the sun’s energy using the “Net Metering” program with your utility. Grid-tie is also the most cost-effective way to use the sun’s energy. The BCUC required BC electrical utilities to offer Net Metering to their home and small business customers starting in 2004. If you are a customer of Fortis BC, Nelson Hydro, or BC Hydro, there are net metering program applications online and the process is fairly simple. Oso Solar can help you with this process as part of our service when you buy a system through our company.
(NEW! Be sure to learn about the NRCAN grants for solar. See “Incentives/Grants”)
Grid-tied solar employs photovoltaic panels (PVs), aka. solar panels or solar modules to create electricity when sunlight strikes their surface. This electricity flows additively across individual silicon crystalline cells in fine conductors to junctions of wiring and on to an electronics device know as an Inverter that matches the electricity from the solar panels (DC) to the electricity which is flowing in the utility power (AC) being fed to your house.
The “Grid” is referring to the fact that the utility has a power transmission grid that is similar to our roadway grid. Like the roadways, power can get on and off at many different locations. When you have a Grid-tied solar power system producing more electrical current than your home or business is using, that extra current pressure will flow out through your meter to the nearest electrical load or user (your envious neighbour that doesn’t have solar). As electricity passes out through your meter it is counted as “Outflow” and you are credited for that energy in how many kilowatt-hours you put on account. A kilowatt-hour is a rate measure of 1000 watts flowing for an hour. After sundown, the meter is counting the energy flowing into the house/business from the utility and recorded as “Inflow”. The utility prints out your total inflow and your total outflow on each bi-monthly bill. Each utility has its own billing format. Annualized Net Metering means there is an anniversary date in the early spring. On the anniversary date, your banked energy from the preceding summer/fall should be used up. We size the system to never exceed your total annual energy consumption. Over-sizing solar is not financially prudent in BC.
The simplicity of “Grid-Tied” solar is there are no batteries that have a limited life and require other intermediate pieces of safety and regulating hardware. This makes Grid-tied the most inexpensive solar electrical option to install, now costing as little as $2.25 per rated watt installed compared to battery-based systems that cost more than $7 per watt. The Return On Investment also known as “ROI”, would: (1) Depend on the cost of electricity you are avoiding purchasing; (2) How optimal your solar exposure is; (3) The quality of the hardware you choose to install; and (4) Ease of installation at your location. When you buy a system with Oso Solar we do not normally charge extra for the system design and the power output estimating. With rising energy rates and dropping solar module costs, the ROI is generally below 15 years, with equipment lifetimes of 20-40 years.
The drawback with grid-tied direct PV systems in the rural Kootenays is no back-up power during fairly frequent grid power outages. There is one inverter product we install that will continue to keep a dedicated plug-in energized if there is adequate sun during an outage, which is likely in a summer outage during the daytime. For back-up power during power outages, you can find more information by following this link: Grid-Tied Solar With Battery Back-up