Purchasing a solar system is a a great energy solution in this day and age. The most recent photovoltaic (PV) systems and solar panels are long-lasting, simple to use, and offer massive energy savings.
In this blog, you'll must learn how to properly design your grid-tie solar system to meet power demand patterns without oversizing your PV array if you want to get the most out of it.
To get the most out of your solar installation, follow these steps to understand how to analyze your solar demands, receive a size estimate, and choose the appropriate panels. Knowing your objectives can help you determine solar panels you'll need for your house.
Why Sizing Your Home Power Backup System is Important?
The solar industry refers to the amount of power produced by solar generators as its “system size.”
When we state that a system is 4 kW in capacity, we imply that it will consistently generate 4 kW of solar electricity.
A system's size also indicates how much solar energy will be generated there—for example, on a house's roof—under actual operating circumstances. On a roof, a 4 kW system, for instance, would produce about 20 kWh of energy on average each day.
The majority of portable solar panel systems used in houses nowadays range in size from 4 kW to 8 kW. The wattages of all the solar panels in the system are simply added together to determine the system size. For instance, a system with 8x 400-watt solar panels has a system size of 3.2 kW.
How to Determine the Right Size for Home Backup Power
Note down the average use on your power bill. Look for “Kilowatt Hours (or kWh) Used” or a phrase to that effect, then take note of the duration indicated (usually 30 days). If the kilowatt hours on your account are not indicated, find the meter readings and deduct the earlier measurement from the most current one.
You need daily and hourly usage for the calculations. Your reply will be given in kW. (And in case you're curious, a kilowatt-hour is the sum of the amount of electricity you consume at any particular time and the entire amount of time it is utilized.)
Your desired daily average for calculating your solar demands is your daily energy use on average. To meet the majority, if not all, of your power demands, your solar system must produce that many kilowatt-hours.
It's crucial to remember that solar panels don't function at their best all the time. For instance, the effectiveness of your system may momentarily decline due to weather conditions. Therefore, to make sure you can produce all the clean energy you want, experts advise adding a 25% “cushion” to your intended daily average.
The number of solar panels you require may be determined by calculating the hourly energy needs of your family by the peak sunshine hours in your region, then dividing the result by the wattage of a panel.
You can use the peak power requirements to estimate your system size, and the number of solar array panels.
How many hours of sunlight can you expect in your area?
As solar power generation is based on incident sunlight on the PV panels rather than heat, it is necessary to know how many hours of direct sunlight the panel or panels will be exposed too throughout the day. The amount of energy you can get from solar electricity at an off-grid site depends on its location and the time of the year.
In general, the northern hemisphere receives more sunshine from April through September, when there is a direct sunling from nine in the morning until three in the afternoon.
When a solar PV panel is pointed directly towards the sun, it generates the greatest electricity. A solar panel's orientation is crucial since it determines where it will be placed and how much sunshine it will get on average over the period of a day, a month, or a year. The majority of houses and gardens, fortunately, have adequate solar access and roofs that are frequently free of anything that may shade the solar panels.
You must be aware of the peak sun-hour number for your position in order to calculate the solar insolation, which is a measurement of the intensity of the sunlight that is impacting the Earth at your location. It's crucial to have a suitable solar location so that the PV panels can receive strong sunshine every day of the year. Additionally, it guarantees that you are using solar energy more efficiently. This may often range from 4 hours in the winter to 8 hours in the summer, depending on the season.
Let's assume that January, when there are only 4.8 hours of sunshine each day, is the month with the lowest solar insolation for our specific region. As a result, the total peak power produced by sunshine in January will be equal to 1800 watt-hours divided by 4.8 hours, which equals 375 watts-peak. If necessary, this might be rounded off to 400Wp.
Size of Storage Batteries
Unfortunately, the sun doesn't always shine, particularly at night, thus backup is needed.
We will need batteries to access that electricity after the sun sets so that we may power the house at night, in the winter, or during times of low solar insolation.
You must decide the battery capacity for the solar backup generator that will last you throughout the day and night.
Determine the number of consecutive overcast days during which the home will require electricity from the batteries.
Solar Charge Controller
All solar power systems with backup batteries should be equipped with a solar charge controller to avoid overcharging of batteries.
The two variables employed in sizing of solar charge controller are voltage and current. The solar controller should supply the necessary DC voltage and accept the maximum power generated by the solar panels.
To protect the controller from being harmed by excessive solar panel current or power, the industry standard 1.2 de-rating factor is provided for systems in continuous operation. The short circuit current of the solar panels over has a value of 6.20A. With four solar panels rated at 6.20A apiece, the solar charge controller's rating should be 30Amps with 12 V rating.
Unfortunately, since appliances need 240 VAC to function, this setup will not be able to power large TVs, home computers, fridges and freezers, etc. The sinewave inverter will be required to convert the 12 DC power to 240 volts AC (alternating current).
The inverter should be sized 20–25 percent larger for safety. A DC to AC inverter with a power output of roughly 400 watts would also be necessary if we also wished to power our electrical equipment with 240VAC.
Additional Considerations With Load Calculations
You may size a solar power system to meet your home energy demands using the information above. However, if your utility offers a net metering scheme that permits energy resale or variable billing rates, be aware that there may be other elements to take into account.
Utilities that charge time-of-use (TOU) fees are a typical application case. Electricity charges increase under TOU billing between the hours of 5 and 9 PM to account for increasing demand when people return from work or school and use reaches its day maximum.
Installing solar panels facing the west may be a good idea if your electricity company levies higher TOU fees. West-facing panels may be more cost-effective overall since they will provide electricity later in the day, countering higher TOU rates during the peak power demand period, even if south-facing panels produce more kWh of energy.
To get the most out of your solar panels, check the specifics of the net metering scheme in your area to determine whether you need to adjust the size of your solar system.
Final Remarks
Any solar system's main objective is to partially or entirely replace your demand for electricity with free and green energy from the sun. The amount of your energy demands that a solar system will be able to meet will depend on a number of things, such as how much electricity your home (or other site) uses, how efficient the system you install is, and where your home is located.
Sizing a solar system can be challenging, particularly if you're putting one in a new house, an RV, a mountain lodge, or you don't know what your home's energy requirements.
Contact Bluetti to learn more about their vast selection of portable solar panels as well as other solar goods like batteries and solar power plants. Select the goods that you believe are best for you. You can select portable solar solutions that best meets your requirements. We have portable backup solutions that range from 600 watt to up to 3kW. You can buy multiple inverters to power your entire home with our solar solutions.
