Solar Power Calculator

A solar power calculator on your website and let your leads configure the number of panels they need, get a price estimate on the system, and learn how much they will reduce their energy bill.

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What is a Solar Calculator

A solar power calculator is a useful tool that helps people design solar power systems, estimate prices, and predict energy savings.

It can quickly calculate different solar energy concerns such as:

  • Panel sizing and system pricing
  • Power consumption estimates
  • Energy output and capacity
  • Installation costs
  • Electric bill savings
  • Return on investment
  • Payback periods or break-even points
  • Solar financing
  • Other solar power design and financial considerations

Our DIY calculator builder lets you easily create any type of solar power calculator you want with no coding at all. You can use all the same equations and formulas you have in Excel and Google Sheets to price solar power packages and jobs. Our calculator builder gives you lots of editing and customization options so you can easily change layouts of our pre-made templates or design a new one from the ground up.

How to Calculate Solar Power Payback Period

Solar calculators are most often used to help customers understand how a solar power system can lower their electric bills. The calculated savings can then be used to estimate how many years it will take to see a return on investment, or what is known in the solar energy industry as the payback period. ROI is one of the most important considerations people have when deciding on whether or not solar energy is right for them.

A very simple way to calculate the payback period for solar power is to take the total cost of the system and divide it by the estimated annual savings on electricity costs.

Total System Cost ÷ Average Annual Energy Cost Savings = Payback Period (Years)

To calculate annual savings just subtract the new average electric bill with the average of the old bill and multiply it by 12 months.

(Old Electric Bill - New Electric Bill) x 12 months = Annual Energy Cost Savings

Example:

Let’s say a solar power setup costs $10,000 in total after accounting for federal and local incentives. This new solar array is able to cut down the electric bill in half from $200 to $100 a month, which adds up to $1,200 in savings per year.

($200 - $100) x 12 months = $1,200 in savings per year

To get the estimated payback period just divide the $10,000 with the estimated energy savings of $1,200 a year.

$10,000 ÷ $1,200 = 8.33 years

This sample solar power system will have paid for itself In roughly 8 years and 4 months, and will continue to save you money for many years to come.

How to Calculate Solar Power System Size

Every solar power system should be properly sized to suit a customer’s specific requirements. Solar power calculators are invaluable tools when it comes to determining how big the solar panel array should be so that it can reliably power essential electrical appliances, especially if the system is off-grid.

There are lots of factors to consider when choosing a solar power system. The more prominent ones include:

  • Energy and kWh requirements
  • Solar array size
  • Number of solar panels required
  • Solar panel efficiency
  • Battery capacity
  • Sun exposure (solar hours per day)
  • Roof area (square footage) and angle

It’s hard to take all these specifications and data into consideration all in one go, especially for someone who’s new to solar energy. But a well-designed calculator can make short work of the task and give out estimates and recommendations quickly.

To calculate your energy requirements, check how many watts an electrical appliance consumes. Multiply the wattage by the number of hours it’s used per day and you get a number of watt hours it needs per day.

Watt Consumption x Hours per Day = Watt Hours per Day

Add up the watt hour usage for your most important appliances and devices to figure out how many watt hours you’ll need from your solar power system per day.

Example:

Let’s get the total energy usage for these appliances.

Solar table

For completely off-grid operation, we’ll need a solar power system that can deliver at least 6.6 kWh per day. If you want to reduce your electric bill by half, you’ll need a system that can produce roughly 3.3 kWh per day.

For any solar power system, you’ll need to account for variances like cloudy days and other less than ideal situations so it’s better to oversize to compensate for any unforeseen circumstances.

Solar savings calculator

The above solar savings template is rather technical and detailed. You can however explore multiple directions in showcasing the potential solar savings. The solar calculator below is a more playful, yet informative calucaltor to showcase solar savings.

How do I compute solar output?

A solar panel’s output is rated in watts and can range from a couple of watts for portable use to over 400 watts for high output models. To calculate a solar panel array’s total output you need to first check each panel’s wattage rating and multiply it by how many hours of sunlight it gets everyday.

Solar Panel Wattage Rating x Sun Hours per Day = Panel Daily Output

To get the entire panel array’s total output, simply add up the daily output of all the solar panels in the system.

Panel Daily Output x Number of Panels = Solar Array Output

Example:

A solar panel array with six 250-watt solar panels that gets an average of 5 hours of sun per day can produce up to 7,500 watt hours of energy.

250 watts x 5 hours x 6 panels = 7,500 watt hours or 7.5 kWh

This solar array is a good match for the example discussed in the previous section which required 6.6 kWh per day. It also has additional capacity to compensate for efficiency losses and spikes in load, and also replenishing the battery bank.

How do I calculate solar energy capacity?

When people think of solar power capacity, they’re probably wondering about how many hours or days a solar-powered electrical system will last in case of a power outage. This is of course dependent on not just the total output of the solar panel array, but more importantly, the size of the battery bank.

While solar panels can provide power to a device without being hooked up to a battery, a battery bank can store any extra electricity the panels produce and provide electricity when the sun’s not out. It’s also easier to power high wattage appliances with a battery bank when a solar array’s total output is not enough.

Batteries used in solar power systems are typically 12 volt, 24 volt or 48 volt varieties and are rated in amp-hours. These are then hooked up to an inverter so that the electricity can be converted from DC to AC to power household appliances.

Since batteries are rated in amp-hours, a 120 amp-hour battery can deliver a constant 5 amps for 24 hours. Alternatively, it can also supply 20 amps for 6 hours.

To power an appliance that draws 165 watts from the wall purely on 12 volt solar battery power for 10 hours will require 1,650 watt hours or 1.65 kWh of electricity.

165 watts x 10 hours = 1,650 watt hours

Remember that Watts = Volts x Amps. So taking the total power consumption and dividing it by the voltage of the battery system will give you the necessary battery amp-hour rating.

1,650 watt hours ÷ 12 volts = 137.5 amp hours

But solar power batteries aren’t supposed to lose more than 50% of their rated capacity so you’ll need to multiply the amp-hour rating by at least 2 to avoid premature battery wear.

137.5 amp hours x 2 = 275 amp hours

Your battery bank needs to have at least 275 amp hours to be able to power the 165 watt appliance for 10 hours straight. If you need it to reliably last for 24 hours, you’ll need to have 660 amp hours of capacity.

How many solar panels will I need?

To quickly estimate how many individual panels you’ll need for your solar installation, take a look at your average monthly electric consumption and divide it by 30 to get your daily average.

Let’s say your monthly bill shows that you average around 450 kWh monthly.

450 kWh ÷ 30 days = 15 kWh daily consumption

Now, let’s try to figure out how many 250-watt solar panels you’ll need to completely run on solar power.

Calculate each panel’s daily energy production by multiplying the watt rating with the number of hours it gets direct sunlight, also known as peak sun hours. Most places get at least 4 hours per day so let’s try that.

250 watts x 4 hours = 1,000 watt hours or 1 kWh produced per day

To cover your daily power consumption, you’ll need at least 15 250-watt solar panels.

15 kWh daily requirement ÷ 1 kWh total energy per panel = 15 panels

Solar loan calculator

You can offer a solar loan calculator to determine the monthly payments and total interest customers will pay toward a solar loan.

Solar panel systems have high upfront costs. This is offset by the savings on the utility bill. If your business offers solar loans to finance the panels, a solar loan calculator can help your customers determine how much they can afford to borrow. The solar loan calculator can also give an estimate on the monthly payments toward the loan and how much total interest is due.

Benefits of a Solar Power Calculator

Let’s take a quick look at the benefits a solar power calculator can bring.

A website calculator improves user engagement

Adding a calculator widget to your website instantly makes it more dynamic and interactive.

A solar power calculator is very effective at catching people’s attention and compels them to spend more time on your site to play around with the numbers on their own. When people use online calculators, there’s always an element of anticipation and excitement involved which translates to better brand recognition and name recall.

You can add different options and settings to your calculator so that it can handle a wide range of solar power requirements and specifications. This not only makes your solar calculator more engaging to use, but also makes its results more precise and accurate.

A calculator form gets you more inquiries and leads

Convincing people to click on your call-to-action button is much easier if it’s placed next to an interactive calculator.

When visitors see that you’re providing a useful resource and you’re making it easy to access hard-to-find information, they’ll form positive associations with your brand and will start to trust you more. After getting results from your calculator, they’ll be more willing to enter their contact information to either book an appointment, request for a quote, or sign up to your marketing emails.

Lead follow-ups and nurturing will be easier because the calculator has already done some of the preliminary work with respect to setting the right expectations. It’s already answered a lot of their basic questions as far as sizing, savings and pricing are concerned. This leads to a significant uptick in successful conversions in a relatively short amount of time.

Your website gets better SEO results and more traffic

People who end up on your solar calculator are less likely to just hit the back button or close the browser to move on to the next page on their list.

At the very least, it will buy you a couple more seconds as they try to figure out what your calculator is all about. This will have a dramatic effect on your bounce rate which search engines like Google use to determine the quality and relevance of your website and domain.

Over time, you’ll see more site traffic and your page rankings will start moving up on the search engine results as your calculator and website becomes recognized as a very useful online resource.

You can also quickly rise to the top of the local and mobile SEO results for specific keywords if you’re one of the few solar companies with a useful calculator.

A solar calculator strengthens your value proposition

Potential clients and customers who are interested in putting up a solar power system have many things on their mind and will often gloss over different sections of your website without fully grasping your messaging.

A calculator lets you easily break down complex concepts that would normally require hundreds of words, many infographics, and lots of hours to fully understand. With just a couple of clicks and keystrokes, calculators can quickly help people better visualize different scenarios on their own. This gives your value proposition a lot more context and helps your audience better understand the tangible and intangible benefits that your products and services can deliver.

Once your visitors and target audience have heard you out, the journey from visitor to lead becomes much shorter, which directly translates into more sales and growth.

A website calculator saves you time and money on marketing and customer service

Even a very basic solar energy calculator can positively affect different aspects of your business.

When you let people freely use the formulas and calculations you normally use to provide estimates and answer questions, you and your team will spend less time explaining the same things over and over again to every new lead that you get. Instead of constantly replying to emails and fielding phone calls left and right, you can free up resources for more important business needs.

Potential customers also won’t have to wait days for an email or phone call just to get a simple question answered if they can find out on their own using your solar calculator widget. A quick response leads to less frustration and will often keep them adequately satisfied until you have time to properly address their concern. This helps create a positive image for your business and makes your targets more receptive to your marketing campaigns.

A calculator form generates specific market data

Our calculators don’t just crunch numbers for your visitors, they also do double duty as extremely effective lead magnets and lead generation forms.

If they click on your calculator’s call-to-action, we can not only collect their contact information but also the info and variables used with the calculator. This gives you more insight into the type of customer you’re attracting and what most people are looking for. It’s the type of invaluable market data that can help you steer your marketing and business operations in the right direction to meet people’s needs.

We’ve also made it easy to collect and aggregate customer data by including easy ways to connect with popular CRM platforms and databases with our calculator builder’s many integrations, so you can further analyze the data using your preferred methods.

How do I add a solar calculator to my website?

We’ve designed lots of different calculator templates to get you started on the right foot. If you see a calculator style you like, just click on ‘Start this template’ and you can start editing and customizing it to your liking.

To better understand the different options we have available, visit our Help section. If you want to create your calculator from scratch we suggest heading over there first to see all the detailed instructions and walkthroughs.

Once you’ve opened up our calculator builder, it’s pretty similar to using a website builder. It doesn’t require you to know how to code and you can just drag and drop different form elements with your mouse. All you’ll need is the ability to edit the HTML code of your website so you can add the calculator widgets you’ve created.

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