- 1. Solar Technology
- 2. System Design
- 3. Solar Products
- 4. Economics
- 5. System Installations
- 6. Misconceptions
Solar energy takes advantage of the sun’s rays to generate heat or electricity. It is an infinitely renewable resource and unique for its ability to generate energy in a quiet, clean, and consistent manner.
Photovoltaic cells are comprised of a semiconductor material, most commonly silicon. Adding common doping agents like phosphorous and boron, create conductivity within the cell and activate the movement of electrons. Doping each side of the crystal lattice in dissimilar elements attracts “free floating” electrons to one side, creating voltage potential.
Sunlight on photovoltaic modules produces direct current (DC) electricity, which is converted to alternating current (AC) by a device called an inverter, which is then wired into your main service module where it feeds your internal power grid.
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.
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.
There are various technolgies at different levels of development that is currently in the works in the industry. However, the most prevalent technolgies are listed below.
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 polycrystal silicon block and are slightly lower in efficiency, but also lower in cost per watt. Polycrystalline silicon is the “chicken nugget” of silicon, made by combining many individual crystals. They are easy to spot because they have an uneven color, usually blue.
Thin film – These are made by depositing a thin layer of very finely powdered silicon (amorphous silicon) or other photovoltaic material, on a substrate. These are much lower in efficiency that crystalline cells, and somewhat cheaper per watt. They are a good choice for large ground mounted utility scale solar arrays where real estate is plentiful. Their low efficiency makes them undesirable for commercial and residential applications because they consume a large amount of roof space compared to mono or poly modules.
Solar modules are known to last 40 years or longer. Typical guarantees of a solar module include ten years workmanship and materials warranty and a 20-25 year performance warranty. The typical PV module performance warranty will guarantee 90% of rated production for 10-15 years, and 80% for 20-25 years. Solar modules are designed to withstand hail, severe wind and weather conditions assuming proper installation.
The technology used in commercial modules has been in production for over 20 years. Improvements have been gradual year over year. There are some promising developments in laboratory solar cells but nothing imminent that is deployable in real-world conditions.
The use of solar energy is growing rapidly, with global installed capacity increasing from 5 GW in 2005 to more than 140 GW in 2014, led by Germany, China and Italy. Capacity is doubling every 2.5 years, and has exceeded 300 GW by 2016.
Solar PV is a mature technology, and widespread adoption is happening because the price has fallen so dramatically. In 1980, a solar module cost $75 per watt. In 2014, it cost $0.75.
In 1998, the installed cost of household solar PV cost $11 per watt. By 2014, it had fallen to $3.50 to 4 per watt.
In 2014, a utility-scale solar installation costs as little as $1.50 a watt in Australia, Texas and California, which converts to a 30-year levelized cost of 9 cents kwh. In Ontario, the utility-scale price is $2.00 – $2.50 a watt.
In Canada, Ontario leads other provinces with 1,235 MW of installed solar PV in 2014 and 939 MW under development.
Ask for an estimate from a solar installer.
Typically the best return on investment is when you target the average power in watts used during the month with the lowest electric bill.
A typical solar module of 250W will measure about 17 square feet. Depending on installation factors, the required square footage of roof space will be somewhat larger than simply the area of the modules. Based on your information, once our engineering department has determined the required angle, shading factors, etc. we can give you a more accurate number.
Take a look at the position of your home on its lot and particularly your roof. Ask the following questions:
1. Is there good southern exposure? Orienting solar modules to the south maximizes the effectiveness of energy collection.
2. Is the exposure free of trees or buildings that could shade the modules or drop debris on them?
3. What is the pitch of your roof? Most roofs, from flat to 60-degrees can accommodate photovoltaic modules.
Absolutely, if you are good with roofs, tools and electrics. We always suggest our customer to get instruction from professionals. It will help you increase the production results. And more importantly, it will keep your system safe and sound.
No. There is no commanding reason why taxpayers money need be used to incentivize solar PV. However, with Vancouver commiting to reaching 100% renewable energy, we must further incentive the proliferation and supporting structures for solar in BC.
Net metering is an accounting method to accurately track electricity sent back to the grid. It allows utility customers who generate electricity on-site, usually from a solar PV rooftop system, to run their meter backward by sending the excess electricity generated back to the grid, or utility company. In turn, the utility company must pay the retail rate for the electricity sent back to the grid.
Yes. BC Hydro’s net metering program has been described as the best in Canada, both for its technical accuracy and for its simplicity. Fortis BC also offers net metering. Your solar installer will tell you what you need to know.
To participate in BC Hydro’s Net Metering program, your PV System must comply with the following key requirements:
- Have a nameplate capacity of up to 100 kW;
- Be owned by and located on the premises of a residential or commercial customer;
- Comply with the technical requirements contained in the Net Metering Interconnection Requirements.
Incoming useable sunlight varies by time of day, time of year and location on the earth. British Columbia has a moderate average annual solar resource, with nearly three times the energy available in July and August compared to December and January.
Over the year, a one-kW PV system located in Vancouver will generate approximately 1,000 kWh. Northwest B.C. has less solar resource, where one kW of installed photovoltaic will generate between 800 to 900 kWh per year.
In contrast, southeast B.C. has the best solar resource, and one kW of installed photovoltaic will generate 1,200 to 1,300 kWh per year.
In contrast, in Germany, which recives less sunshine per year than BC, solar has contributed 30 GWh of power in 2013, powering 5.7% of Germnay’s grid.
Moreover, the efficiency of solar PV increases in colder temperatures and is particularly well-suited for Canada’s climate.
You can estimate how much a solar electric system may cost if you determine your current energy needs and costs and compare against your future anticipated use. Once you have a sense of how much energy you use, you can evaluate the cost of purchasing and installing a solar technology.
Each of the major banks will provide ‘green’ financing options through small business loans; both secured and unsecured. For further clarification contact your financial service provider.
According to BCHydro, an average household (2 adults & 2 children) uses 28-30 kWh per day.
Although southern exposure increases the effectiveness of a residential solar power system, your home may still work for solar power without having south facing exposure. To further analyze the viability of solar on your property, contact us.
By general rule of thumb, the ideal angle and orientation is 30 Degrees facing south. However, moderate deviations from ideal does not significantly impact energy production. Deviating from ideal angle and orientation only reduces performance by 5-10%.
The location of your home and the local climate will play into where you place and how you install your PV system. Wind speeds, heavy snow loads, and saltwater can all affect a solar array. Understanding how those inputs affect performance will determine the types of mounts or how the arrays are angled.
We frequently coordinate our work with roofers to ensure warranties remain in force and the PV system installation also comes with a 5-year warranty which includes roof integrity.
The solar modules need sunlight to produce electricity so a ‘sticky’ snowfall that blocks the sun will certainly reduce the power output until it melts or is removed. Once exposed to bright sun, the modules heat up and will shed any snow cover. A good system design will maximize power output with partial snow coverage. Also you may have some other benefits: Albedo effect (reflection coefficient) increase radiation and less temperature → more efficiency.
There are no moving parts to wear out in a solar PV system. A semi-annual inspection and optional cleaning is all that is required.
Solar modules installed on your roof convert sunlight to electricity throughout the day. Any electricity that you do not use immediately is put into the power grid. This excess solar energy offsets your energy use at night when the system is not generating electricity. The result is lower utility bills and more control over your energy costs.