Now that solar power is becoming a cheaper and easily available alternative energy option for homes, homeowners need to understanding that there are a lot of considerations and technical concerns that they don’t know.
Putting solar panels on your roof does not necessarily translate into energy savings and in fact, may lead to a rather painful journey of disappointment. This is because most consumers skip the most important step of any solar power project – System Design!
The number of factors to be considered when designing any solar power project makes the design process a demanding and time-consuming activity for consumers and contractors – but extremely NECESSARY.
The main reasons why you need a solar PV design before installing solar panels are:
1. Not every home is a good candidate for solar energy.
2. You may still experience a power outage during a power cut.
3. Not all solar energy systems are created equal.
4. Wrong system sizing is always an issue with most solar projects
5. The voltage differences of all the system components need to be harmonized.
6. The battery bank backup needs to be properly sized, configured and located
Because Designer PV believes in teaching buyers about solar power, we’ve put together this list of important facts that many solar contractors and installers would rather not tell you until you have made the deposit.
With this knowledge, you will be better placed to make an informed decision on whether or not to go ahead and install solar.
Let’s dive in and look into what each of these reasons means.
1. Not every home is a good candidate for solar energy.
Believe it or not, a good number of homes are actually not a great candidate for solar energy and would not necessarily benefit from installing solar panels.
Some solar installers and contractors will, unfortunately, skip the system design step, install solar panels on your roof and you’ll never see any energy-saving or rebate benefits at any point in the near future.
Some of the factors that these installers may fail to consider are:
- You need to make other energy-saving measures first to become more energy efficient before installing solar e.g better insulation, replacing thermostats and heaters with more efficient heat pumps.
- Shading on your roof due to other taller buildings or trees heavily reduces any solar power generated by the panels – trees may have to be cut.
- Your roof may not be able to structurally support the extra weight from the solar panels – roof inspection is needed.
- Your entire electrical load (especially heaters, pumps, power tools, swimming pool heaters) may not be a good candidate for powering with solar.
2. You may still experience a power outage during a power cut.
Most homeowners think that when they install solar panels they will still have power during a grid outage. Unfortunately, that is not true unless they install an adequate battery bank to store the electricity.
Most home solar power systems are actually tied to the grid for net metering. This ensures that you draw some power from the grid when the solar panels produce less power than you need and send excess power to the grid when your panels produce more.
For these reasons, the solar contractor and installer need to properly size your essential loads (lighting, A/C, TV, kitchen equipment) and design an equally adequate battery back up to power them during a power outage.
3. Not all solar energy systems are created equal.
You need to understand that a solar design that works well for one home may not work at all in another.
As solar energy has become more mainstream and cheaper, many people especially electrical contractors claim to have knowledge of solar installation. But that is far from the truth!
Even when installing solar panels on your roof yourself (DIY), it is still a very expensive investment, and you should ensure you do thorough research and have a proper solar design and installation plan before buying anything.
Any solar energy project must be custom-built to the energy needs and environment it is being installed.
The customized solar energy design maximizes the power produced by the installed solar panels to optimally power your home considering your energy load, location, your roof size, local fire codes, peak sunlight hours and maximum out.
For instance, if the solar project is not properly designed, you may buy an inverter that is too small to handle the power produced by the panels in case you need to add more in the future or the arrangement of the panels may violate local fire codes and safety requirements.
Even worse, the installed design may not be the best. Without a proper design, the solar panel stringing configuration may not be optimized.
With a proper solar system design, the same number of panels could significantly produce up to 30% more power and reduce the installation and maintenance costs.
4. Wrong system sizing is always an issue with most solar projects
Properly sizing a solar project is more complicated than most people think or assume.
To inexperienced technicians or if you are installing the panels yourself, system sizing may seem as simple as checking your power bills, determining your energy load and buying the number of solar panels that cover that load.
But that is a dangerous approach that overlooks several other environmental and hardware factors that need to be considered and affect the performance and durability of your solar power system. These factors include array stringing, climate, panel orientation and angle, roof shading, panel ageing, etc.
For instance, the power output of solar panels drops at a rate of about 1% per year but your home’s energy load would most likely increase every year. Likewise, the climate (temperature, wind, rain, dust) also dictates how much energy is produced by the panels.
That’s why you should have a proper solar system design and installation plan to account for these other factors that you may ignore before you order the solar panels.
5. The voltage differences of all the system components need to be harmonized.
All the hardware components of a solar power system (panels, inverter, batteries and charge controller) operate at different voltages.
For example, a 315 Wp panel could have an operating voltage of 36V, the inverter output at 48 V and each battery at 12 V.
The solar system has to be properly designed to ensure that all the component voltages are right and match. The design also considers cabling and temperature which may have an effect on the system voltage and performance.
Failure to harmonize the input and output voltages of the solar panels, inverter, batteries and charge controller may lead to equipment damage or worse.
6. The battery bank backup needs to be properly sized, configured and located
The most common problem we have experienced with battery banks is a mismatch between the batteries and the charging source.
As long as your system includes batteries, the solar panels should be designed to produce enough power to both supply the loads and charge the batteries to capacity within the sunlight hours.
The charge controller also needs to be properly sized to ensure that the batteries do not overcharge or drain so much of their currents. This prevents battery damage and preserves battery life.
The battery type, technology, configuration, and location needs to also be carefully planned and design to ensure proper and efficient operation. All batteries are not equal and lack of a proper design could result in premature failure.
Learn more about what a Proper Solar Design Can do for You Here