How much power you’ll need and how much power each type of solar panel produces are important pieces of information to know if you’re considering transferring your household to solar energy. There are many different elements that affect how much power your panels will produce. For example, size, efficiency, and energy conditions will all need to be considered in order to meet your energy needs.
After all, the amount of electricity your solar panels produce will directly impact your long-term savings. You’ll likely want enough energy to cover your electric bill, otherwise it’ll take longer to break even on your solar investment.
In this article, we’ll go over everything you need to know about how much power solar panels produce, how to estimate the amount of power your household needs, and which solar panels would be right for your home. We’ll also cover the major questions about what happens if you generate too much or too little energy.
How is solar power production measured?
Solar power production is measured in watts (W), kilowatts (kW), and kilowatt-hours (kWh). Here is a quick breakdown of what each of these terms mean:
- Watts (W): Watts are a basic unit of power that indicates the rate at which energy is generated or consumed.
- Kilowatts (kW): A kilowatt is equal to 1,000 watts and is most commonly used to measure the capacity of solar panels and solar power systems.
- Kilowatt-hours (kWh): Kilowatt-hours are the amount of energy consumed or produced over a period of time. For example, if a 300-watt solar panel operates at full capacity for one hour, it produces 0.3 kWh.
To calculate how much electricity a solar panel can produce in one day, you simply multiply the power output of your solar panels by the number of peak sun hours in your area. Here is a quick example:
If one solar panel produces 500 W and your area gets five peak sunlight hours, the equation would be 500 W × 5 hours. This makes the answer to the question “how much electricity a solar panel can produce in one day” a simple 2,500 watts. Note that most states within the U.S. receive at least 4.5 peak sun hours per day.
What affects solar panel power capacity?
Most solar panels used in residential settings can produce between 300 W and 800 W per hour. Because of current technology and average peak sun hours, common residential solar panels have an efficiency of around 20%.
Your panel’s capacity depends on a variety of factors. Your location, the direction and tilt of your roof, and the materials that solar panels are made of will all affect efficiency and capacity. Understanding these elements can help you optimize the performance of your solar panels. Let’s dive in.
Location
Perhaps most obviously, the amount of sunlight your solar panels get will be the most critical factor in how much energy they produce. Some states see more sunlight than others. For example, if you are in California or Arizona, your solar panels will likely be more effective. But even if you don’t live in a super sunny place, you can still benefit from solar.
Roof tilt and direction
The way the solar panel is directed at the sun can also affect their exposure to sunlight, and thus its efficiency. In the northern hemisphere, including the United States, the ideal position for panels would be facing south to capture the most sunlight throughout the day. Because of how efficient solar technology has gotten, your home can benefit from solar even if you don’t have a south-facing roof.
The angle of your solar panels also matters. An easy way to determine how much to tilt your solar panel is to use your line of latitude. If you prioritize these two factors when installing your solar panels, you’ll be able to significantly increase energy output. By choosing an installer like Trinity, you won’t have to figure this out on your own. We’ll design the most efficient system for your roof using specialized technology.
Solar power cell materials
The design of your solar panels is another major factor for solar panel efficiency. Solar panels can be divided into three main categories: monocrystalline solar panels, polycrystalline solar panels, and thin-film solar panels. At Trinity, we use monocrystalline solar panels because they’re highly efficient and durable. Here is a quick breakdown between the three options:
- Monocrystalline solar panels:
- Made from a single silicon crystal
- Dark, non-reflective colors
- More efficient (18-22%)
- Long lifespan
- Better in high temperature and shady conditions
- Polycrystalline solar panels:
- Made from multiple silicon fragments melted together
- Blue, reflective panels
- Moderately efficient (15-18%)
- Shorter lifespan
- Less efficient at higher temperatures
- Thin-film solar panels:
- Made from lightweight photovoltaic materials
- Flexible and portable
- Less efficient (10-12%)
- Shorter lifespan
- Good for unique installations, such as RVs
How to estimate power output to your house
Now that you have an in-depth understanding of how solar power production is measured and how to judge the different factors that affect their efficiency, it’s time to jump into the next step: determining how much power your household uses.
- Identify appliances and devices that use electricity. This can include lighting, electronics, appliances, heating and/or cooling devices, etc.
- Make sure to note the wattage of each appliance. This can typically be found on a label or in the appliance manual.
- Determine how many hours you use each device on an average day and multiply each appliance’s wattage by this amount.
- For example, if a 200-watt television is used four hours a day, the equation so far would be 200 × 4 = 800 watt-hours per day.
- Convert to kilowatt-hours by dividing the daily watt-hours by 1,000.
- Following along with our example, 800/1000 = 0.8 kWh per day.
- Multiply the daily kWh usage by 30 days to get an estimated monthly usage.
- Following along with our example, you would then do 0.8 × 30 = 24 kWh per month.
- Add up each of your appliances and devices kWh/month to get a total estimated energy consumption for your household.
If you have a larger home, or a home with more people in it, you’ll likely require more energy to be produced by your solar panels. It’s also good to remember that seasonality can affect power consumption, such as using more air conditioning in the summer or heating in the winter. When thinking about solar power storage, consider these fluctuations into your calculations.
The easiest way to determine the ideal-sized solar system for your home and energy needs is by talking with a Trinity Solar Expert. They’ll do all the work for you, factoring in your energy usage and budget.
What happens if I produce more solar power than I need?
Your solar system will be designed to match your energy needs as closely as possible. However, if it produces more than you need, any excess energy is sent to the electric grid. If you live in an area with net metering, you can actually be compensated for the energy you put into the grid.
There are also solar storage options available to couple with your solar panels, such as solar batteries. These can save your excess energy to use when sunlight and solar energy production may be low. We highly recommend checking your utility company’s policy on net metering with home solar and battery storage before deciding which solar power system is right for you.
Get a free quote
Now that you understand the factors involved in designing a solar system tailored to your home, it’s time to get your custom design. Schedule your free, no-obligation consultation with a Trinity Solar Expert today.
