What is solar energy?

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. 

How do solar photovoltaic cells work?

In layperson terms, photovoltaic cells are comprised of a semiconductor material such as silicon. Added to the silicon are the elements phosphorous and boron which create conductivity within the cell and activate the movement of electrons. The electrons move across the cell when activated by the sunlight’s energy into the electrical circuit hooked up to the solar panel. 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 board where it feeds your internal power grid.

How much does a solar electric power system cost?

The cost is directly related to the size of system you would require. Greenstar Power technicians will assess your requirement based on your current electricity usage. A 2kW grid tied solar electric system will cost approximately R45,000. That total includes the cost for all components – solar panels, panel mounts, and inverter – and labour associated with installation. It does not however, include battery back-up for power outages

What is a grid-tied solar electric system?

The two options that you could look at is off-the-grid or grid-tied. Off-the-grid requires that you are able to produce enough electricity on your own without needing to obtain electricity from the regular energy supplier like Eskom or your municipality. Grid- tied means that your solar electric system generates some of your electricity need and you still make use of some electricity from the regular supplier as well.

How much will I really save on my electricity bills from a home electric solar power system?

Of course this is a relative question. It depends, in part, on how much electricity you use and how efficient the appliances are that you operate. That said expect to generate excess electricity in the summer (when days are long) which can potentially offset the energy you use from the grid in the winter. A combination of energy efficient appliances and light bulbs can help reduce your homes electricity bill substantially.

What’s the difference between solar photovoltaic and solar geyser systems?

While both types of solar systems capture energy from the sun, solar photovoltaic systems use photovoltaic panels to produce electricity. Solar geyser, or thermal, systems capture sunlight to heat water for domestic use, to heat a swimming pool, or for a radiant heating system.

What are solar hot water systems?

Solar geyser systems, broadly termed solar thermal systems, use the sun’s energy to heat water. Solar geyser systems can be used to heat a hot water tank or to warm a home’s radiant heating system. Swimming pools and hot tubs use a modified solar geyser system for heating water. As an alternative to heating your water with a geyser, consider a heat pump. It uses 70% less energy to heat up your water.

More information on heat pumps at http://www.greenstarpower.co.za/product_category/heat-pumps

How do pool heating systems work?

Pool heating systems use a modified solar geyser system to capture the sun’s rays to heat your pool or hot tub.

How much maintenance do solar energy panels require?

Solar photovoltaic panels require little maintenance – no need to wash or dust. It is, however, important to place panels where they will remain clear of shade and debris. Thus you will have to wipe them off if too much snow or leaves fall on them.

Solar geyser collection arrays don’t need much attention either. It does help to periodically use a window wash brush, biodegradable soap, and water to clean the tubes.

Can I use a financing system?

Yes. Consider using a home loan for the purchase and installation costs of a solar photovoltaic system. Solar energy systems are viewed as a major home energy savings upgrade and there are financial tools out there that reward you for your efforts. Remember, installing a solar energy system is comparable to any other upgrade you might do to your home, such as installing a new deck or remodelling a kitchen. There are also specialist green energy funders in the market that can be considered

Do I need special insurance requirements?

Standard homeowner’s insurance policies usually suffice to meet electric utility requirements. We would recommend that you consult with your insurer as they may have preferred product choices.

Will I need a building permit to install a solar energy system in my home?

No. Provided that the installation complies with certain parameters, no building permit is required.  You might, however, need a certificate from your municipality in respect of electricity generation. Your installer should be able to assist you in this matter.

When should I seek a solar professional?

Although solar energy systems work in parallel with conventional residential electrical and plumbing systems, there are quirks in the process well suited to seeking out professionals who specialize in solar power installation. Solar installation professionals can help you determine the type and size of system most suited for your needs.

What should I ask a solar professional installer?

Solar professional installers can take the guess work out of installing a solar power system. Whether you are considering solar photovoltaic, solar geyserr, or solar heat for your pool, a solar pro can help you determine the type and size of system that will work best and guide you through the process.

Why is it important to get multiple bids?

As with any major purchase, it’s helpful to compare costs and information. Seeking information from multiple professionals can provide constructive advice, set realistic expectations, and help you fine-tune the design that will work best for your application.

How can I calculate the cost and payback time from a solar power installation?

You can estimate how much a solar electric or solar hot water 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 one or both of the technologies.

How long will it take to install a solar power system in my home?

Planning, configuring, and doing any custom ordering for your solar energy system can
take up to a few weeks. However, the installation process itself can typically be completed
in only a few days.

What components do I need to install a grid-tied solar electric system?

You will need a photovoltaic array to capture the sun’s energy, an inverter to convert
the direct current (DC) produced from the photovoltaic cells into alternating current (AC)
used by your home, and a house utility meter – called a net meter – that can record both the electricity produced from your home’s power system as well as any power you may use off the grid. These three system components are then connected through a series of wiring. The photovoltaic panels are secured to your roof with panel mounts or are installed on poles that can be adjusted for sun angle.

What is a net meter?

Net meters look very much like other outdoor meters with one notable exception – they spin both forwards and backwards recording both the power produced and power used.

Do I need battery backup for my solar panels?

It’s a nice to have as it can cover you during power outages. A backup battery bank can add as much as 25% in cost to a residential solar PV system. It’s not necessarily more efficient either – a same sized solar array will yield about 7–10% less energy if it’s battery-tied than its grid-tied counterpart.

Though you will remain tethered to your local utilities’ grid, you will not have to worry about not generating enough power. You also gain the advantage of offsetting rising utility costs. Most solar photovoltaic experts do not recommend adding a backup battery system unless there is concern about a long utility outage or the residence is in a remote location.

How much space do I need for a solar photovoltaic system?

In bright sunlight, a square foot of a conventional photovoltaic panel will yield 10 watts of power. That’s a helpful rule of thumb for calculating a rough estimate of how much area you might need. For example, a 1 KW system may need 10 – 20 square m of area, depending on the type of PV module used.

How many solar panels do I need for an electric solar power system?

The size of the photovoltaic system is correlated to your home’s energy-use needs, available space for a system, and overall costs for the system components and installation. Solar contractors in your area can help determine the best size for your solar photovoltaic system.

How much shading is too much for solar photovoltaic panels?

Unfortunately shading a photovoltaic system dramatically decreases its output. Just shading the bottom row of wafers alone amounts to an 80% reduction in efficiency. So above all, don’t shade your array!

How do I know if solar panels will work on my home?

Take a look at the position of your home on its lot – and particularly your roof. Ask the following questions:

  1. Is there good northern exposure? Orienting solar panels to the north maximizes the effectiveness of energy collection.
  2. Is the exposure free of trees or buildings that could shade the panels or drop debris on them? Shading photovoltaic panels dramatically reduces their effectiveness.
  3. What is the pitch of your roof? Most roofs, from flat to 60-degrees can accommodate photovoltaic panels.

Do I need to have north facing exposure to have a solar energy system?

Although northern exposure increases the effectiveness of a residential solar power system, your home may still work for solar power without having north facing exposure. Seek advice from a professional solar designer or installer to ensure success.

What other factors are important to consider when installing a home solar energy system?

The location of your home and the local climate will play into where you place and how you install your solar electric or solar geyser system. Wind speeds and salt water can all affect a solar array. Understanding how those inputs effect performance will determine the types of mounts or how the arrays are angled. A Greenstar Power Solutions consultant is quite knowledgeable about your local conditions and can help you design that which  works well for you.