Frequently Asked Questions Solar Photovoltaic Energy
PV Modules (Solar Panels): PV modules take sunlight and convert it to electricity. The modules produce DC electricity.
Solar Combiner: PV modules are wired together in series to meet the grid tie inverter’s input voltage requirements. These groups of modules are called strings. Multiple strings are combined in parallel to create one circuit from solar.
AC Mains Panel and Utility Meter: Regulates power consumption and production via net metering. Net metering means you only pay the difference between what you produce and what you use.
AC Disconnect: Requirement under the Canadian Electrical Code to have the ability to disconnect all sources of power production.
Grid Tie Inverter: An electronic device that converts direct current (DC) to alternating current (AC). This device provides AC electricity to your main service panel as solar creates it in DC.
Frequently Asked Questions
What is “grid-tie”?
When a power system is grid tied it is connected to the utility provider such as BC Hydro. By connecting to the grid you do not need batteries to provide peak loads and you can sell excess electricity to BC Hydro through the net-metering program. Batteries can still be part of the system if you wish to have a backup for use during power outages.
Can PV be installed on my roof, regardless of the roof material?
Generally, yes. Solar can be installed on all types of roofing including metal, asphalt, cedar, tile and flat.
What if the PV system can’t fit on my roof, or what if my roof isn’t facing south?
If your roof is not a suitable location for photovoltaics, we can mount the modules on racks or poles. Racks are typically stationary but they can be made to tilt for seasonal optimization. Poles can be stationary however poles are often used with trackers, which allow the modules to follow the suns path through the day.
How big of a PV system do I need?
That depends on your goals and if you are connected to the grid or not. Grid tied systems can be as large as you want. Often budget and the percentage of offset are influencing factors in the final decision. Off-grid systems are sized based on a load calculation, which comes down to a balance of lifestyle and budget.
What happens if I produce more electricity than I am using?
With a grid-tie PV system any energy produced that you don't use is sold to BC Hydro through an agreement know as Net Metering. BC Hydro will credit you for electricity that you provide to the grid, and if you have a large system or use very little energy, you could be net zero. Net zero means over the course of the year you produce all of the energy that you will consume.
What is the return on investment for solar photovoltaics?
As with any renewable energy system, this is a longer term investment, but the amortized capital cost of a solar electric system equates to 11+ cents per kilowatt hour over a 30 year lifespan. It won’t be long until that cost is on par or is less than what we pay to the utility! This means that while you're essentially paying for your electricity upfront, instead of every month, you will never pay less for electricity in BC than you do today. And as electricity rates are already approved to increase dramatically over the next few years when those rates increase, the payback for solar electric systems shrinks.
The bottom line is that we need to look at a few factors to understand the real return on investment (ROI), such as escalating energy costs, increased value and peace of mind. It would be great if gas was always going to be $1 a liter or electricity $0.09/kWh, but we have seen periodic price spikes in energy cost more than ten times the inflation rate and the price of natural gas in BC double between 2002 and 2007. Also consider that the capital investment and reduced operating cost of a solar electric system installation will often pay back at resale! In this day and age it's impossible to put a price on environment. The extra electricity we consume and fossil fuels we burn, while good alternatives are out there, is just digging a bigger hole for future generations. With this in mind, isn't the promise of reduced energy bills and cleaner living worth something?