How Do Solar Panels Work? An Expert Guide

The technical answer to this is that photovoltaic (PV) cells within solar panels convert the sun’s energy (electromagnetic radiation or EMR) into DC electrical energy. An inverter then transforms the DC electricity into AC electricity, making it suitable for use in your home.

But do you want to know more about how solar panels work in practice? This fascinating renewable energy source has many components that help make electricity possible. At Eco Happy, our mission is to assist UK households with their energy requirements. This guide provides comprehensive insights on harnessing the power of solar panels in the UK.

How Solar Panels Generate Electricity

To benefit from the sun’s energy, you need the correct tools for the job. Below are all the components needed in a solar module system to generate and harness electricity – whether you want to stay on-grid or transition to an off-grid lifestyle.

Solar panels and components

Solar panels (solar module)

Solar PV panels are the most recognisable part of a solar power system. The panels are made of conductive materials and photovoltaic cells (PV cells) that collect and turn light into DC electricity. Solar PV cells create electrical charges in response to photons (light) reacting on the cells’ internal electrical field.

To learn more, check out our in-depth article on how solar panels are made.

For solar panels to get as much sunlight as possible, they are installed on rooftops or ground-mounted arrays where there is unobstructed sunlight.

Most popular types of solar panels:

• Monocrystalline – made from single-crystal silicon, these are highly efficient and work well in low-light conditions.
• Polycrystalline – made from multiple silicon crystals – a cheaper alternative to monocrystalline panels.
• Thin-film – has layers of different photovoltaic material and is more affordable than mono- and polycrystalline panels.
• Solar thermal panels – harness sunlight to generate heat instead of electricity.

Solar inverter

When you install solar panels, you need an inverter to convert the electric current. Solar power works by turning the sun’s energy into alternating current (AC). AC is the type of electrical current used in homes, but electronic devices and appliances require direct current (DC) to function. An inverter helps with the AC/DC conversion.

To maximise the efficiency of your solar power system, it’s essential to match the inverter’s capacity with the appropriate number of solar panels. For example, if you’re considering a 3,000-watt inverter, you might wonder how many solar panels you would need to support it effectively.

Battery bank

Batteries store excess electricity generated by solar panels for use when sunlight is unavailable, such as during the night or on cloudy days. They also provide backup power during grid outages or emergencies. A charge controller is essential to regulate electricity transfer to your battery system, ensuring that the batteries are charged efficiently and safely.

When setting up your solar energy system, it’s crucial to choose the right size solar panels based on the capacity of your batteries. For example, if you’re using a 100Ah battery, you need to determine the optimal solar panel size to charge it effectively. Similarly, different requirements apply if you’re charging a 200Ah battery. Selecting the correct panel size helps maximise your system’s efficiency and reliability.

Grid connection

A grid-tied inverter is needed to connect to the government electric grid. This pushes excess electricity back to the grid or draws power from it when there isn’t enough solar power. You need to ensure that you connect the inverter in a way that complies with your local regulations.

Metering equipment and monitoring system

Metering equipment measures your electricity production and consumption. It also monitors system performance and calculates your energy savings. Metering equipment can include production, consumption, and net meters.

A monitoring system provides real-time data on your solar system’s performance, including energy production, consumption, and efficiency.

Wiring and electrical components

Conductors, cables, and connectors are needed to link the solar panels, inverters, and other components, as well as safety devices such as circuit breakers, fuses, and surge protectors. These will protect the system from overloading and facing electrical faults.

How Many Solar Panels Do You Need?

In the UK, the average household is estimated to use around 3,700 kWh of electricity a year. How many solar panels you need depends on the amount of electricity you use. Generally, a 3-4 kW solar array can cover up to 50-70% of your electricity needs.

How to prepare your home to transition to solar power

In practical terms, before you can install solar panels your roof must be in good condition and meet local regulations. You could also consider upgrading to energy-efficient appliances, like boilers, to get the most out of your solar setup. Read our in-depth article to find out if your roof is suitable for solar panels.

Integrating Solar Panels With UK Energy Systems

As we mentioned above, there are a handful of regulations in the UK that you need to know and follow before starting with solar panel installation.

Approval from your Distribution Network Operator

A District Network Operator (DNO) is a company in your residential area that licences electricity distribution. DNOs own, operate and manage the national transmission network that supplies electricity to the UK.

If you want to install a solar panel system in your home or small business, you are required to register it with your local DNO. Usually, your installer will do this for you, but it helps double-check that you comply with local regulations.

Earn money back from the SEG

The Smart Export Guarantee (SEG) allows you to earn 15p per kWh from excess renewable energy, including solar power, by exporting it back to the grid. This scheme applies to various renewable technologies like wind, hydro, and solar hot water systems. To participate, you must sign up with an energy supplier offering SEG tariffs.

Connecting solar panels to a hybrid system

You can combine your solar photovoltaic system with other renewable technologies. The most common options in the UK include heat pumps or solar water heaters. These work well together in a home that has high heating needs. For example, solar panels can power a heat pump, which makes the whole system more eco-friendly.

You could also simply use your solar panels to power an electric heat pump. By combining solar energy with other technologies, you can save energy, reduce costs, and help the environment.

Benefits of Solar Panels

Reduced electricity bills

Solar panels can significantly reduce your electricity bills – the sun’s energy is free! With the ever-increasing energy prices, solar power provides a stable and cost-effective alternative to electricity supplied by the grid. The initial investment may be costly but is well worth it in the long run.

Financial incentives and returns

Installing solar panels allows you to take advantage of various financial incentives and returns. Government schemes, such as the SEG, pay you for the excess electricity generated and exported back to the grid.

Additionally, there are tax incentives, grants, and subsidies available to support installation, including the Feed in Tariff (FiT) and NIROCs.

Helping the planet

Choosing solar doesn’t only benefit your wallet, but also contributes to energy conservation. Solar power produces no greenhouse gas emissions and minimises your reliance on fossil fuels. Reducing your carbon footprint is always worth it for the future and well-being of our planet. 

Are Solar Panels Right For You?

Many wonder if solar panels are worth it, especially in the UK. Although solar installation is initially quite expensive, it eventually pays itself off in savings. It also lowers your energy bills upfront, plus you could earn money from the SEG. These are just a few of the reasons why you should consider switching to solar energy.

However, to truly determine if installing solar is right for you, you will need to weigh up the overall pros and cons.

For some intriguing insights, check out our article on 12 interesting facts about solar panels. It offers valuable information that could influence your decision-making process.

FAQs

Do solar panels work on cloudy days?

The good news is that they do. It’s no secret that the UK faces some gloomy days, so would solar panels still work? Solar cells can generate electricity when it’s cloudy and raining, as there is still light. They’ll just work less efficiently. Batteries would help sustain your electricity needs in this case.

How do solar panels work with your electric bill in the UK?

You save money on your monthly electricity bills when you use solar because you use less or no electricity from the national grid. You can also get paid by the SEG if you supply your excess solar electricity to the national grid.

If you’re wondering whether you’ll still need to pay for electricity after installing solar panels, check out our guide for more information.

How long do solar panels last?

Generally, the lifespan of a single solar panel is around 25 to 30 years. Other components, like the mounting structure, wiring, and electrical parts last for 20-30 years. The inverter usually has a lifespan of 10-20 years, depending on the quality.

Is it better to have more or less solar panels?

Starting with fewer but more efficient solar panels is a good idea. You can always add more later if you need to. This way, you don’t use up too much space unnecessarily.

Can I mix solar panels with different voltages?

Mixing solar panels with different voltages is generally not recommended. When solar panels with different voltages are connected together, it can lead to inefficiencies. This is because the system will operate at the voltage of the lowest panel, which means that the higher voltage panels won’t be operating at their optimal capacity. Additionally, mismatched voltages can cause imbalances in the electrical flow, potentially leading to overheating or other issues.

Final Thoughts

Solar panels are brilliant! They’re made of semiconductor material and use solar radiation to generate an electric current. Solar energy is truly something to admire, with its many components, uses, and benefits. If you’re still unsure, take a look at our guide on the reliability of solar energy. If you’re interested in installing this system, contact Eco Happy for a free quote today.