How Does Solar Energy Work? The Lowdown

Topic: solar projects Read Time: 6 mins
Landowner type:
Independent landowners | Institutional landowners
Energy: Solar
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Have you been scratching your head trying to find an answer to the question, “How does solar energy work?” If so, you’ll want to join us as we discuss everything you need to know about this powerful renewable energy source.

If you’re interested in getting a solar project on your land, you might be wondering exactly HOW solar energy works. After all, you don’t want to host a large-scale project without understanding what’s going on behind the scenes.

In this detailed rundown, we’ll cover absolutely everything you need to know to answer the question, “How does solar energy work?” We’ll dive into everything from solar irradiance levels and construction materials to Grid connection and thermal panels.

Now, let’s get straight to it.

Simply put, solar energy is radiant energy emitted by the sun and captured by photovoltaic panels. This energy usually comes in the form of thermal or electrical energy. This is then transferred to our homes and businesses as usable alternating current (AC).

The process of creating usable solar energy starts with having the right tools and equipment.

This usually includes:

  • Solar panels or modules
  • Inverters
  • Metres or measurement equipment
  • A connection to the Grid
An infographic showing how solar energy works

Now that we’ve covered the absolute basics, let’s dig a little deeper.

Photo showing the solar irridance in the UK

It probably comes as no surprise that not ALL of the UK receives the same levels of sunlight each day. And if we compare the sunniest and least sunny places in the UK, you’ll see just how different irradiance levels can be.

Eastbourne is leading the way as the UK’s sunniest area and boasts around 8 hours of sunshine each day in June. Following closely behind is Bognor Regis, clocking in 7.7 hours of sun on an average summer day. This is any sunshine that clouds don’t obscure, making it highly usable, “bright” sunshine.

Comparatively, the Scottish Highlands come in with relatively low sunshine levels (with the North West generally performing poorly). If you’re looking for a shocking example, Cape Wrath received just 36 minutes of sunlight in January of 1983. 

Monthly totals in the North West of England are usually around 150 hours each month on average in June. This comes to just 5 hours of sunlight a day during the country’s sunniest period.

So, it’s probably unsurprising that most solar farms are located in the Southeast and Southwest of England (where sunshine is generally more forthcoming).

We’ll also mention that according to PVGIS (Photovoltaic Geographical Information System), the difference in electricity produced from a 4kWp solar system on a south-facing 30-degree pitched roof in John O’Groats and Lands’ End is 840 kWh/year. These calculations consider solar irradiance and direction (two essential factors to think about when considering land suitability for solar panels). Over the lifetime of a solar project, that’s a considerable difference.

Now that we’ve figured out what solar energy is, let’s delve deeper into the question, “How does solar energy work?”

The process usually starts with photovoltaic solar panels that manufacturers make using semiconductors (typically silicon) and glass casings. The glass casings are less crucial to energy production, but they keep the panels protected and durable.

The photovoltaic panels that form the electric charge get “sandwiched” between silicon layers. This gives each slice a positive or negative electrical charge. Usually, manufacturers seed phosphorus into the top silicon layer (with a negative charge), and seed boron into the bottom layer (with a positive charge).

An infographic showing the insides of a solar panel

When sunlight hits these solar cells, it knocks electrons loose from their atoms. This process creates an electric field (AKA: the photoelectric effect) and makes the current needed to produce electricity. Wires capture this feed of direct current and funnel it to a dedicated inverter. The inverter then turns it into an alternating current that we can use day-to-day.

Photo showing the different types of solar panels

Although most solar panels work in the same way, the most popular types of solar panels are monocrystalline and polycrystalline.

Monocrystalline cells typically comprise a single silicon crystal, while polycrystalline cells are made from fragments or shards of silicon. Since the monocrystalline panels are “purer,” the larger, unbroken surface area offers more room for electrons to move around. This makes them significantly more efficient than polycrystalline panels, but it also makes them considerably more expensive.

The other popular solar panel type is a thin-film solar cell. You usually find these on buildings with oddly shaped roofs. They have a thinner and more flexible texture than monocrystalline panels but are less efficient (generally between 12 – 14%).

Solar thermal panels are nowhere near as common as photovoltaic panels, and people usually use them to heat swimming pools. If you’re wondering why, it’s because they use solar energy to provide renewable hot water for things like showers and taps.

But that’s not all.

You can also use them for:

  • Industrial process heating
  • Distillation
  • Desalination
  • Air conditioning
  • Space heating

This heating system features solar furnaces that use the sun’s heat (instead of light) to make electricity. They feature mirrors that capture and focus large amounts of solar energy into a single area to make steam. This process creates steam that powers a generator and produces electricity.

One major positive point that comes from using solar thermal panels is that they’re around 70% efficient (which is considerably higher than the efficiency rates of regular solar PV panels).

However, they also have a shorter lifespan and are exclusively used for water heating. So, they’re unlikely to be appropriate for landowners and developers looking to mount large-scale solar projects.

Connecting to the Grid is vital to any solar project (particularly large-scale ones). After all, the electricity has to go somewhere once the energy is passed through an inverter and transformed into an alternating current.

In home-based systems, monitoring tools show how much power is being sent to the Grid. These tools help determine monthly billing figures and any relevant credits that might apply. For large-scale projects, a developer will apply for a Grid connection in advance of the project’s getting up and running. The project will then connect to a specific point on the Grid, aptly called a Point of Connection.

Indeed, there are.

In 2023, the first photovoltaic solar array that connected directly to the National Grid was successfully energised. Enso Energy and Cero Generation connected this project on behalf of a 50 MW Larks Green Solar Farm near Bristol.

Before this, all of the UK’s solar farms were connected to one of 14 local networks. These lower-voltage regional grids carry power from the central Grid to homes and businesses. Although this direct connection process is in its early stages, this may become the norm over time. This would let you transport renewable energy over much greater distances and boost the efficiency of the UK’s overall energy provision system. So, it’s undoubtedly a positive move forward.

If you’re trying to answer the question, “How does solar energy work?” you’ll probably be wondering how cloud cover affects things. While it doesn’t make panels completely defunct, cloudy conditions can certainly make your panels less productive.

On cloudy days, the panels absorb whatever irradiance they can get through thick cloud cover. As the clouds block a considerable amount of sunlight, this will naturally be less than what reaches the ground on a clear day. The same issues apply to shading from trees, unexpected fog, snow cover, and anything else that might block the panels.

Because these conditions can seriously impact a project’s productivity, site operators should monitor and manage the site to check for any new obstructions. This should prevent anything from getting in the way of the panels and reducing the site’s overall income potential.

As you can see, solar energy is a fascinating form of renewable energy, but site operators and landowners need to make sure it stays productive. By removing obstructions and keeping the panels onsite in tip-top shape, you’ll reap the financial rewards from a site for years to come.

If that sounds appealing, contact the Lumify Energy team to discuss getting a project on your land. Not only will we run you through the process from beginning to end, but we’ll make sure you’re getting the best deal possible from developers. We’ll guide you through lease agreements AND compare your site to similar ones nationwide. The result? You’ll get precisely the payment arrangement you deserve for leasing your land.

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