The Ultimate Guide to Solar Panels

Introduction

Welcome to this guide on solar panels, the innovative technology that harnesses the power of the sun to make clean and renewable energy. With this guide we aim to provide you with knowledge and insight about what solar panels are, how they work, the different types, how to maintain them, the environmental benefits and much more. This guide will equip you, as a business owner, employer, or employee, with all the essential information you need.

Browse the guide at your own pace or open the dropdown menu to click the links to jump to the sections you need the most.

Section 1 – What are Solar Panels?

Solar panels, or photovoltaic (PV) panels, are devices that convert sunlight into electricity. They are composed of multiple solar cells, usually made of silicon, that generate electricity when exposed to sunlight.

The solar panels use the photovoltaic effect. Photons from sunlight excite electrons and they become loose from their atoms within the solar cells. This creates an electric current. The direct current (DC) is then converted into an alternating current (AC) which makes electricity that is suitable for use in our businesses, such as in our electrical devices, including computers, phones, and machinery.

For a more in depth look at how solar panels work, check out our Guide to how Solar panels work.

Section 2 – Solar Panel Types

There are three prominent types of solar panel, which are monocrystalline, polycrystalline, and thin-film solar panels, each has their own characteristics.

Monocrystalline Solar Panels: These panels are highly efficient and are recognised through their uniform appearance. They are made from a single crystal structure, usually silicon, for efficient movement of electrons. Even within a limited space these solar panels have a high-power output and performance, making them suitable for commercial settings.

Polycrystalline Solar Panels (Multi-crystalline Panels): These are made from multiple silicon crystals. Molten silicon is poured into a mould, resulting in a polycrystalline structure. These panels are bluish and have a slightly lower efficiency than monocrystalline panels. Though they are more cost-effective, and they do provide reliable energy generation.

Thin-Film Solar Panels: They are made from depositing thin layers of semiconductor material onto a substrate, these layers are usually made from amorphous silicon, cadmium telluride (CdTe), and copper indium gallium selenide (CIGS). These panels are flexible and lightweight, and although they are not as efficient as other types they perform better in low-light conditions. They also have a low environmental impact during the manufacturing process.

Section 3 – Solar Panel Components

A solar panel system consists of several components that work together to capture sunlight and convert it into usable electricity, these components are:

Solar Panels (Photovoltaic Modules (PV)): The primary component, that consists of multiple solar cells made of semiconductor materials (e.g., silicon) that converts sunlight to direct current (DC) electricity.

Inverters: Inverters convert the direct current (DC) electricity into alternating current (AC) electricity, which can be within our businesses, as AC electricity is compatible with the electrical grid and electric appliances and devices.

Charge Controllers: Mainly used in off-grid systems that utilise batteries for storing excess energy. They regulate electricity flow and ensure proper charging to prevent overcharging and deep discharging.

Batteries: They are essential in off-grid systems, where there is no connection to the electrical grid. They store excess electricity generated by the solar panels to be used during low-light periods or at night. Batteries can provide a continuous power supply and can be used as a backup power system.

Monitoring Systems: These can provide real-time data on the performance and energy production of the solar power system. They track energy generation, system efficiency and environmental conditions. They can also identify issues and inefficiencies quickly to optimise system performance.

Section 4 – Solar Panel Efficiency

The efficiency of the solar panel determines how effectively they can convert sunlight into usable electricity.

Solar panels are affected by temperature, as the temperature rises their efficiency lowers. Higher temperatures can cause electrical components to become resistant, which reduces the flow of electrons.

When a portion of the solar panel is shaded, it can disrupt the flow of sunlight to the affected solar cells, which reduces their output. Even shading from a tree or building can affect the overall performance of the solar panel system. When installing solar panels find an area with minimal shading to maximise efficiency.

Solar panels need to be installed in respect to the sun’s path, for optimal efficiency they should be facing south when in the UK. This orientation will allow maximum exposure to sunlight throughout the day, to allow high energy capture.

The optimal tilt of the solar panel depends on where in the world your business premises are, in the UK this angle is between 30ᴼ and 40ᴼ. Adjusting the tilt angle at different times of the year can also optimise energy capture.

Other factors such as the quality of the solar cells, and the transparency and reflectivity of the glass can affect the panels efficiency. Cleaning the panels regularly is important as dirt, dust and debris can build up and reduce efficiency.

It is worth noting that higher quality solar panels can achieve 20% efficiency or higher where lower cost panels efficiency will fall between 10-15%.

Section 5 – Solar Panel Installation

Solar panel installation requires careful planning and adherence to the guidelines to ensure efficiency and safety. Solar panels are typically installed on rooftops or as ground mounted structures, see below the key considerations for both types.

Rooftop Installation

• Before installation a structural assessment must be carried out, to ensure the roof can support the weight of the solar panels and mounting system. A structural engineer may need to be consulted.
• The roof type and material will determine which mounting system will need to be used. Common systems include ballasted, penetrating, and flush-mount systems.
• The wiring layout needs to be carefully considered, including the distance between the panels, inverters, and electrical connections. Both for safety and efficiency.
• Appropriate safety equipment needs to be installed, such as guardrails or edge protection to ensure safe rooftop access for installation, maintenance, and potential repairs.

Ground-Mounted Systems

• Choose an area with optimal sunlight exposure and minimal shading. Factors such as soil condition, drainage and obstructions need to be considered before installation.
• A solid foundation needs to be prepared before installations, such as concrete footings or ground screws to support the mounting structure. Always follow the manufacturers guidelines for assembly.
• Trenches need to be dug to bury the electrical conduits that connect the solar panels, inverters, and electrical system together. Ensure proper grounding and the electrical code requirements must be adhered to.

To prevent unauthorised access implement security measures such as fencing. Make sure there is enough space for maintenance, upgrades, and repairs.

Section 6 – Safety Measures

Comply with the guidelines, electrical codes and regulations when designing and installing the electrical components of the solar power system. Ensure that appropriate grounding and protective devices are used to mitigate the risk of electrical hazards.

Fire safety guidelines should be followed, such as using fire safe materials around wiring and conduit, and properly cleaning around the solar panel area. To minimise the risk further install a rapid shutdown device for emergencies.

All electrical components, disconnect switches and circuit breakers must be clearly labelled for easy identification for maintenance and emergencies.

Ensure compliance with local building codes, zoning regulations and utility interconnection requirements and obtain necessary permits.

Section 7 – Solar Panel Maintenance

Monitor the solar panel system’s output regularly to make sure it is generating the required amount of electricity. This can be done through the inverter display or monitoring software. A significant drop in output could indicate a problem.

Visual inspections should be carried out to identify any signs of damage, such as cracks, loose connections, or debris. Check for signs of deterioration and wear to the wiring, electrical components, and mounting system.

To maximise efficiency, keep solar panels clean of dirt, dust, and debris, as they can prevent the panels from absorbing sunlight. Follow the manufacturers guidelines for cleaning, which usually involves a soft brush/sponge and mild detergent. Avoid abrasive materials. Before cleaning make sure you carry out safety measures. Turn off the system, wear gloves and non-slip shoes, and work during cooler hours.

Ensure you educate yourself on the common issues that can affect solar panel performance, such as shading, inverter faults and loose connections. Refer to the manual or consult a professional if faults occur.

Consider scheduled professional periodic maintenance to assess the solar power systems overall health. Professionals will be able to carry out in depth inspections and electrical tests to address any maintenance or repair needs.

Snow, leaves, and excessive shading, caused by the changes in weather can lower a solar panel’s performance. Take measures to remove snow and leaves and to trim trees to mitigate these issues. If unsure hire a professional.

Keep a record of maintenance activities, system performances and notable observations. This can be valuable for troubleshooting and warranty claims.

Section 8 – Solar Panel Sizing

To meet your energy needs effectively, the number and size of the solar panels needs to be considered. You must begin by assessing what your average energy consumption is. You can do this by reviewing your business’s energy bills and checking your monthly and yearly usage. This will help to identify the size of the solar power system needed to meet your energy needs.

Evaluate the amount of roof space you have, take into consideration orientation, possible shading, and obstructions.

Research the irradiation levels in your area, meaning the amount of sunlight received per unit of area within a given period. Different regions will experience different levels of solar irradiation. Consider weather patterns and seasonal variations as these can also affect the solar panels performance.

Solar sizing tools or consulting a professional can calculate the system size required to meet your business’s energy goals. This calculation considers factors such as efficiency, average daily sunlight hours in your area and potential losses due to shading or system inefficiencies.

Ensure to balance the system size with a budget or financial goals. A larger system may produce more electricity, but it will also have a higher upfront cost. It may be best to research whether the UK Government are issuing any financial incentives or grants.

Consider whether you would like to expand in the future, or if you are aware that your energy needs will increase, install a slightly larger system.

Section 9 – Solar Panel Financing

Finance Options

In the UK there are several options available to make solar panel installations more affordable and accessible. These are:

Purchasing: Buying solar panels allows businesses to own the system and benefit long term, with savings on energy bills. The initial cost will be higher, however, over time the reduction in electricity costs and potential income from feeding energy back to the grid will pay off the investment.

Leasing: This allows businesses to install solar panels without the big upfront cost. The solar company owns and maintains the panels, whilst the customer pays a fee for the electricity generated. This can be useful for those that don’t want to handle the maintenance or who have limited funds.

Power Purchase Agreements (PPA): PPAs involve entering an agreement with a solar company to purchase the electricity generated at a predetermined rate. The company will install, own, and maintain the system. This gives you immediate savings on electricity costs, without the upfront cost.

Incentives and Rebates: The UK Government offers incentives and rebates to promote the installation of solar panel installations. The Feed in Tariff (FiT) scheme provides payments for the electricity generated and fed back into the electrical grid. The Smart Export Guarantee (SEG) ensures customers receive payment for any surplus energy exported.

Solar Panel Cost Analysis

Upfront Costs: This includes the purchase price of the solar panel, the inverters, mounting equipment, installation costs, and necessary permits. This cost varies on the manufacturer, size, and component quality. In recent years the cost has significantly decreased making them more accessible.

Return on Investment (ROI): This measures the financial benefits gained from the investment in solar panels. It is influenced by the upfront cost, available incentives, and the local solar resource. After the ROI period, the energy generated becomes effectively free, creating long-term savings.

Long-Term Savings: Generating your own electricity will reduce your business’s reliance on the electrical grid. Therefore, savings will be made on electricity bills. The amount of savings depends on the size of the system, energy consumption and local electricity rates.

Financing Options: Financing options are available to make solar panel installations more available, including outright purchasing, solar loans, leasing and purchasing power agreements (PPAs). Make sure to research and choose the right financial option for you.

Energy Prices: The cost of the grid-supplied electricity affects the financial benefits, if electricity prices rise the solar panel’s economic viability increases as well as the savings through self-generation. However, if electricity prices lower, this may impact the payback period and overall financial benefits.

Net Metering

Through net metering programs, excess electricity generated by solar panels can be offset and fed back into the grid, to earn credits or compensation for their contribution. For this to be applicable the system must be connected to the electrical grid.

This excess electricity is measured through a bidirectional meter that tracks the energy consumed from the grid and the energy exported to the grid.

Any compensation or credits received will usually be applied to the solar panel owner’s electricity bill. If the amount of excess electricity exceeds the imported electricity during the billing period, credits will be passed onto to future bills. Therefore, when energy produced by the solar panels is low, the credits can be used to offset the cost of energy imported from the grid.

Net metering provides a financial incentive to solar panel owners and allows them to maximise the value of their solar power system as no energy goes to waste. Whilst also promoting the use of a sustainable and renewable energy source.

It is important to note that incentives will differ throughout the UK, depending on your region or utility company. Make sure to consult your energy provider or local authorities to get more information regarding availability, eligibility, metering arrangements, compensation rates and other guidelines.

Section 10 – Solar Panel Integration

Grid-Connected Systems: These are the most common and straightforward in integration systems. The solar panels generate electricity during the day and feed the excess power into the electrical grid. When electricity isn’t being produced or is being produced at a low level, electricity is drawn from the grid. These systems use inverters to convert the DC current electricity to usable AC current electricity.

Off-Grid Systems (Standalone Systems): These systems are not connected to the electrical grid. They are commonly used in remote areas where access to the grid is limited or expensive. These systems also integrate batteries or charge controllers. Stored energy in the battery during the day is used to power electrical appliances during times of low sunlight or at night.

Hybrid Systems with Battery Storage: These systems combine the benefits of grid-connected and off-grid systems. They use both solar panels and batteries to store excess energy for later use. During the day the solar panels charge the batteries, and surplus energy is sent to the grid. Stored energy can then be used during outages or during the evenings.

Integrating solar systems into existing electrical systems has a range of benefits including reducing costs, decreasing reliance on fossil fuels, and lowering carbon emissions.

Section 11 – Solar Panel Application

Commercial and Industrial Application: Businesses are using solar panels to offset their energy consumption and lower their operational costs. Clean energy is generated through large rooftop installations or ground-mounted systems. These systems help businesses to reach their sustainability goals.

Solar Farms (Utility-Scale Solar Installations): These involve a vast number of solar panels over a large area of land, such as open fields or desert regions. They generate a significant amount of clean energy on a large scale that feeds directly into the power grid.

Portable Solar Panels: They are lightweight and are easily transported, and they can be used to charge batteries or power small devices, such as phones and laptops, directly.

Solar-Powered Devices: Solar panels can be integrated into numerous devices to provide self-sustaining power, including to solar-powered lights, water pumps, ventilation systems, and phone chargers. Solar energy reduces the reliance on the electrical grid and allows these devices to be used in remote locations and during power outages.

Solar-Powered Vehicles: Solar energy can power electric cars, boats, and drones. The panels are installed to the surface of these vehicles and the sunlight captured is converted to usable energy for direct use to power the motor or to charge a battery. This creates an environmentally friendly transport option.

Section 12 – Environmental Benefits

Solar panels offer numerous benefits, such as reducing reliance on fossil fuels, reducing energy bills, and decreasing carbon emissions. This makes them an environmentally friendly and sustainable energy solution to mitigate climate change. As technology advances these solar panels become more affordable and much more accessible for businesses.

We can minimise our carbon footprints by switching to solar power. Burning fossil fuels releases greenhouse gases, such as CO₂. Solar energy generation reduces these emissions significantly. This also decreases our reliance on fossil fuels, such as coal, oil, and natural gas. By shifting to a renewable source, energy security increases, price volatility reduces, habitat loss and landscape damage decreases, and emissions lower significantly.

Traditional energy sources rely on water-intensive processes, solar energy production, however, requires minimal water consumption. By conserving water resources, solar energy can be the solution to lowering water scarcity and protecting ecosystems that rely on a healthy water supply.

Unlike fossil fuel energy generation, solar energy production does not release harmful pollutants into the air and water that cause pollution and respiratory health problems. By minimising pollution through opting for solar energy, environments will become significantly cleaner and healthier.

Due to solar panels being able to be installed anywhere, available space and unused land can be utilised. This helps to minimise the need for large-scale land clearing and associated loss of biodiversity. Solar farms can coexist with agricultural practices, to promote dual use of land and preserve natural habitats.

Section 13 – Solar Panel Regulations and Policies

The UK has various local, regional, and national regulations, policies, and incentives to support the increase in solar panel installations and promote renewable energy adoption, these include:

Planning and Permitting: Local authorities are important in regulating solar panel installations. Planning permissions may be required, depending on the scale and location of the installation. Local authorities will consider certain factors when evaluating planning applications, including visual impact, conservation areas, and listed buildings.

Grid Connection: Interconnection standards and regulations govern the connection of solar panel systems to the electrical grid. Distribution network operators (DNOs) specify the technical requirements for grid connection to ensure safety and reliable integration. These standards cover voltage levels, power quality, and protection systems.

Smart Export Guarantee (SEG): The SEG ensures that customers are paid for any surplus energy they generated that is exported back to the grid.

Renewable Energy Guarantee of Origin (REGOs): REGOs are certificates that are issued to renewable energy generators, such as solar panels, to verify the origin and environmental benefits of the electricity produced. They provide evidence of renewable energy consumption and help businesses meet sustainability targets.

Green Energy Schemes and Grants: Several green energy schemes and grants are offered by the UK Government to support renewable energy projects. These are in place to encourage businesses switch to renewable energy sources and reduce emissions.

Consult with local authorities, energy advisors, or solar installers who can provide up-to-date information and guidance.

Section 14 – Solar Panel Lifespan and Recycling

The lifespan of a solar panel is typically between 25-30 years. Their longevity depends on different factors such as the quality of the materials, the manufacturing process, and maintenance. Over time the efficiency of the solar panels will decrease. Monitor the performance of the panels to ensure optimal operation and identify issues that require maintenance or replacement.

As the number of solar panels increase worldwide, the need to address end-of-life management increases. To minimise their environmental impact, they must be disposed of or recycled properly. This can also increase the recovery of valuable resources, such as silicon, glass, and aluminium for reuse, and to reduce the need for raw materials. Reducing habitat loss, lowering emissions, and preventing the release of potentially harmful substances found in solar panels.

The UK has implemented regulations, laws, and incentives to manage waste, including end-of-life solar panels. These regulations aim to establish collection and recycling networks, encourage responsible disposal practices, and ensure compliance with environmental regulations.