{"id":739,"date":"2021-07-08T14:00:00","date_gmt":"2021-07-08T14:00:00","guid":{"rendered":"https:\/\/aurorasolardev.wpengine.com\/blog\/how-solar-irradiance-is-calculated-and-how-we-made-it-30-times-faster\/"},"modified":"2024-04-29T19:46:35","modified_gmt":"2024-04-29T19:46:35","slug":"how-solar-irradiance-is-calculated-and-how-we-made-it-30-times-faster","status":"publish","type":"post","link":"https:\/\/aurorasolar.com\/blog\/how-solar-irradiance-is-calculated-and-how-we-made-it-30-times-faster\/","title":{"rendered":"How Solar Irradiance Is Calculated\u2013and How We Made It 30 Times Faster"},"content":{"rendered":"

When you sit down to design a solar installation for a prospective customer, probably one of the first things you consider is how much solar energy (irradiance) is available in different locations.\u00a0<\/span><\/p>\n

In today\u2019s blog post, we explain the principles of calculating solar irradiance and discuss some of the computation approaches we employed to make this critical process faster for you.<\/span><\/p>\n

We\u2019ll also talk about why an efficient solar irradiance calculation can save solar installers over $800 per system.<\/span><\/p>\n

If you\u2019re using remote solar design software<\/a>, rather than relying on manual measurements at the project, all you have to do is click a button and the software generates an irradiance map showing the solar irradiance at every point on the roof of your site model.<\/span><\/p>\n

But what\u2019s happening behind the scenes in your solar software to deliver that irradiance map? Do you understand the diverse components that go into the calculation of solar irradiance?<\/span><\/p>\n

While one of the <\/span>benefits of solar software<\/span><\/a> is that you don\u2019t need to think too much about these calculations, it can be helpful to have an understanding of how solar irradiance is calculated to answer customer questions. Here at Aurora, we think about these calculations a lot, and recently our engineers have been working hard on updates that increased the speed of irradiance calculations by 30 times!<\/span><\/p>\n

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An example of a solar irradiance map generated by Aurora solar software.<\/em><\/span><\/div>\n

What is Solar Irradiance?<\/span><\/h2>\n

Irradiance is a measure of solar power. Because power refers to the rate of energy transfer over time (not the total amount of energy delivered), another way of thinking of irradiance is that it quantifies the amount of solar energy that arrives in a particular area in a given moment [Watt\/m2].<\/span><\/p>\n

When that value is converted to express the total amount of energy the area receives over a certain interval of time, say one hour, it is communicated in Watt hours (Wh) or, depending on quantity, kilowatt hours (kWh) per unit of area [(k)Wh\/m2]. This is a measure of insolation.<\/span><\/p>\n

In Aurora, we use the term irradiance interchangeably with insolation and communicate the value in kWh\/M2\/yr. This provides a helpful way of conceiving of the amount of solar energy that will be available to your solar installation over the course of the year, given any shade that is present as well as the local weather patterns.<\/span><\/p>\n

To learn more, check out our blog on <\/span>Key Solar Energy Terms<\/span><\/a>.<\/span><\/p>\n

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Solar Irradiance Maps<\/span><\/h2>\n

When you\u2019re selling solar to clients, it can be helpful to know how their areas are affected by their location in reference to the sun. However, as we\u2019ll get to in the next section, the calculations themselves can be very intricate.\u00a0<\/span><\/p>\n

As a help, we\u2019ve gathered links to some excellent resources for solar irradiance maps that you can find here:<\/span><\/p>\n