Solar energy is the most reliable and powerful source of energy in the world. In fact, the amount of power from the sun that strikes the Earth in one hour is more than the whole world consumes in a year.
Although the use of solar energy is not a new concept, the installation of solar systems in the UK has seen a sharp spike in recent years. This may be due to increased environmental concerns as a result of climate change as well as the increased affordability of installing solar power systems at home.
Currently, the United Kingdom stands 8th in the global ranking for the use of solar energy. With the renewed focus and encouragement of the government to use renewable energy in residential and commercial environments, the UK is well on its way to fulfil its pledge of becoming a zero-emission country by 2050.
Solar Facts
- The UK has 13.26 GW of combined solar PV power capacity, which is enough for 3 million households.
- Solar panels are more effective in temperate regions compared to very hot countries.
- Modern panels work reasonably well in cloudy weather, even though the light on cloudy days isn’t as strong.
- Despite the traditional view that the UK is cold and cloudy, it receives about 60% of the equivalent solar radiation found at the Equator, which means the region is particularly well-suited for solar panels.
- Over 80% of the British people support solar power systems.
Solar power is not simply a clean source of energy, but also a very cost-effective and efficient way to power your homes. Although the use of solar energy in homes is fast becoming an obvious choice, many people wonder exactly how solar power works.
Let’s find out.
The Science Behind Solar Power Systems
To understand how solar panels work, we need to first understand what solar panels are made of.
Solar panels consist of photovoltaic (PV) cells, which catalyse the conversion of raw sun energy into usable electricity. The PV cells are placed between two layers of a semiconductor like silicon, which creates an electric field when touched by sunlight. This is known as the photoelectric effect and is necessary for producing electricity.
However, the energy that PV cells generate is direct current (DC), which is not suitable to power up your home’s electrical appliances. Therefore, you also need to install an inverter as part of your solar power system.
The main function of the inverter is to transform the direct current passing through it into alternating current (AC). This electricity is then sent to the main consumer unit of your house or business. The Consumer unit will make sure that all of your appliances are sufficiently powered by the solar panel system and will send any excess energy to the national grid.
The energy that a solar panel array produces is measured in watts, which is the same unit of measurement used to determine the power usage of your home’s appliances. It is important to know how much wattage your solar array is producing as it can help you determine the energy needs of your home and business.
A solar panel system is also smart enough to switch on and off by itself. Depending on your home’s power usage, it can switch seamlessly between the national grid as well.
Determining the Efficiency of Solar Panels
To determine the efficiency of your solar array, you need to factor in several variables, including the photovoltaic cell efficiency, position of the solar panel on your roof, the location of your home, your roof design, the temperature, and the sunlight-to-shade ratio that the solar panel will be receiving every day. All of these factors need to be considered to ensure that you obtain the right solar panel configuration for your home.
The efficiency of a solar panel is the measurement of a solar panel’s ability to convert sunlight into usable electricity.. The higher the efficiency of your solar panel, the less space it will consume. Although higher efficiency panels are more expensive, if your roof space is limited this option may generate your home’s energy needs more effectively.
In recent years, there have been many advancements in photovoltaic technology, which has resulted in solar panel efficiency increasing from 15% to over 20%. This means an average solar panel is able to produce an additional 370 watts of electricity.
As mentioned above, a solar panel’s efficiency is determined by a number of factors, the most important of which is the PV cell efficiency.
Solar Cell Efficiency
A solar panel is made from PV cells, which convert the sun’s energy into electricity. The structure of the cell and the semiconductor material, which is usually silicone, determines the efficiency of a solar cell. Cell efficiency is calculated as the ratio of the energy output from the cell to the input solar energy. Hence, the design of a solar cell determines how efficient it is.
Panel Design
Solar panels are designed with a layer of glass that protects the PV cells through which the solar energy passes. The amount of energy generated depends on the angle at which the sunlight passes through the cells. In addition, the reflectivity of the glass should also be considered.
Panel Position
The right installation of the solar panel system is crucial to capturing and maximising the use of the sun’s energy. The solar panel’s efficiency will be determined depending on how much sunlight a panel receives.
The Angle of the Roof
The slope of your roof will determine how much sunlight is received by your solar panel array. Despite southern-facing roofs providing an optimal use of daylight, west and east facing roofs also capture early morning and late evening sun and are only slightly less effective. Most residential solar panels are fixed into place, although large businesses often use solar tracking systems that allow the solar panels to be adjusted to compensate for the position of the sun in the sky.
Shade
The efficiency of your solar panels may also be impacted by any structure blocking the sunlight to your roof, including trees or other buildings. Ideally, your solar panels should be placed in such a way that they receive maximum exposure to the sun and avoid any shadows during daylight hours.
Temperature
As previously mentioned and contrary to popular belief, very high temperatures can reduce the efficiency and output of a solar panel system. Even the most efficient solar panels can lose 10 percent of their rated efficiency on very hot days. Depending on where you live, you should get a solar panel that is designed for its climate.
As the UK rarely suffers from extremes of temperature, it is surprisingly well-suited for solar panels.
Will Solar Panels Work in Winter?
Solar panels react to light, regardless of the temperature. This means that during daylight, your solar panels will continue to generate electricity. The brighter the sunlight, the more electricity will be produced. That said, fewer sunshine hours and the sun being lower in the sky will result in less sunlight reaching the panels in winter compared to summer.
Finding Out the Right Size for Your Solar Panel System
Installing a solar panel system requires significant investment and effort. That is why it is important to get it right the first time around.
When determining how many solar panels you need for your array, you need to take into account three factors:
- Your daily energy consumption
- The average daylight hours in your area
- The size of your roof or platform
Solar panels produce different amounts of energy, depending on their capacity and rating. A panel rated at 250-watts will generate 250 watts per sun hour, while one with a higher capacity will generate more energy. That is why your daily energy consumption is the most important factor when determining the size of your solar panel array. To find this out, you need to find out the total kilowatt-hours you use. This can easily be achieved by viewing your monthly energy bill.
As a general guide, the average UK house consumes 3,731 kWh/year. Hence, your solar power panel needs to generate at least this much if you are solely relying on the sun’s energy to power your home.
The size of the roof or platform where your solar panels will be mounted will determine the number of panels that can fit onto your home. This will, in turn, determine how much energy they can generate and at what cost. In addition, the strength and pitch of your roof will also play a part, since it needs to support the weight of your solar panels or position them at the right angles.
In the UK, a 4kW size solar panel is the most commonly used, typically requiring about 12 panels with a surface area of 21.6 m2.
The Most Efficient Types of Solar Panels
The types of solar panels that are available for residential and commercial businesses in the UK depend on their specific requirements. In the solar power market, the most efficient types of solar panels are monocrystalline, polycrystalline, and thin-film solar panels.
These solar panels have different types of PV cells that are designed to produce energy in different ways. It is important to understand that the efficiency of an individual solar cell does not determine how efficient your solar panel system is on the whole.
Monocrystalline Panels
Monocrystalline panels, also known as single-crystal panels, are original, advanced, and the most efficient types of solar panels. Before other methods were used to create solar panels, all solar power arrays were made from monocrystalline panels.
Manufacturing Process: These panels are made from monocrystalline cells created from pure silicon. The manufacturing process is complex and involves silicon crystals being dropped into molten silicon. The crystals are then slowly drawn out, allowing the molten silicon to form a delicate shell around them. This shell is then sliced thinly into wafers, which are cooled down to form PV cells. These cells are then assembled to create a photovoltaic panel.
Efficiency: Currently, monocrystalline solar panels have an efficiency of over 20%.
Appearance: These cells have rounded edges, creating tiny gaps between cells and appear black because of the interaction of sunlight with silicon. However, their frame and backing are made in a range of designs, which means you have the option to choose the ones that fit your aesthetic sense.
Polycrystalline Solar Panels
Polycrystalline solar panels are the more recent type of solar panels in the market, which are also very efficient. They are quite similar to monocrystalline solar panels in that their cells are made of silicon. However, they are made from melted silicon crystal fragments.
Manufacturing Process: During the manufacturing process, the crystals are allowed to melt into molten silicon, rather than being drawn out slowly. These crystals are then allowed to fragment and cool. Once the crystals have cooled, they are thinly sliced into polycrystalline wafers and then assembled to form a solar panel.
Efficiency: Polycrystalline solar panels have an efficiency of between 15% and 20%.
Appearance: Polycrystalline solar panels have cells that turn blue when sunlight hits them. That’s because the sunlight is reflected in a slightly different way compared to monocrystalline solar panels. Their cells are also cut into perfect squares so they do not have any gaps in the corner, which improves cell efficiency. They usually include silverback frames as well.
Thin-film Solar Panels
Thin-film solar panels are the newest type of solar panels in the industry. As their name suggests, they feature thin-film panels and can be constructed from silicon as well as several other alternative materials.
Manufacturing Process: Compared to the type of panels above, the manufacturing process of thin-film panels is less complex, which means they degrade faster. Thin-film solar cells are made by placing the main material between thin sheets of highly conductive material and covered by a layer of glass for protection.
Efficiency: The efficiency of thin-film solar panels is 15% to 22%; however, with advanced solar technology, the efficiency gap is quickly being closed in relation to the more expensive panels. Thin-film panels are commonly installed in industrial-sized solar power plants and large-scale projects.
Appearance: These panels can be easily distinguished by their slim dimensions. In fact, they are 350 times slimmer than panels made from silicon wafers. They may be black or blue depending on which material they are made from.
Although they are still in their early development phase, rapidly advancing technology may potentially result in this type of solar panel being one of the best available in future years.
Aside from the manufacturing process and the appearance, these three types of solar panels have a couple of operational differences, benefits, and uses, depending on their needs. When deciding which solar panel to buy, it is important to consider the cost and efficiency of each solar panel system.
The gap in efficiency between each one is expected to decrease as more advancements are made in the field of solar panels. It is also worth bearing in mind that efficiency alone does not always mean you have the best solar panel system. Other factors should also be taken into account, including manufacturing quality, durability and cost.
In terms of cost, thin-film solar panels are the most affordable type of solar panels, since they are very lightweight and installation is easier. However, they are predominantly used in the commercial market at present.
Monocrystalline solar panels, on the other hand, are the most expensive type of solar panels in the market, since manufacturing pure silicon is a complex and costly process. In addition, the frames and panels of monocrystalline solar panels are heavier, which means a higher cost of installation.
Polycrystalline solar panels were developed to reduce the cost of monocrystalline solar panels and can be an efficient, more affordable option to consider.
Deciding to Install Solar Battery Storage Systems
One of the pressing questions that many prospective solar panel owners ask is whether they should also invest in solar panel batteries. Solar panel batteries offer a lot of advantages and can improve the efficiency of a solar panel.
These batteries store the excess solar energy generated by the panels so that it can be used at a later date. This means you can continue to power your home and business through solar panels even when there is no sunlight and the panels are not actively producing electricity.
An additional benefit is time of use charging. Solar panels generate less solar energy in the winter and a battery can be used to supplement the energy created on a cost effective basis. Some energy suppliers provide significantly reduced off peak tariffs, which solar batteries can take advantage of by recharging on an overnight basis.
Solar panel batteries can also help reduce and even eliminate the reliance on national grid electricity and offer you more cost-saving benefits, as well as are being more environmentally-friendly. Because you minimise electricity use from the grid, you will have substantially reduced electricity bills. In some cases homeowners are off grid – i.e. they have managed to completely eliminate their electricity usage from the grid.
Households that have solar panels with battery storage can use on average about 80% of the energy generated, while households that do not have solar panel batteries use about 50% of the energy generated.
The amount of cost-saving benefits created by installing solar panel batteries depends on the number of solar panels installed, the size of the solar panel battery, and how much the batteries can discharge.
Hence, if you want to save more energy, you would need to install more solar panels with more battery storage. Solar panel professionals can advise you on what suits the needs of your home in the best way and the relative cost.
Advantages of Going Solar
For decades, we have been looking for greener sources of energy as an alternative to fossil fuel. Climate change is a reality; it’s happening at an alarming rate and only by using renewable sources of energy and practicing sustainability can we reduce the impact on our environment.
Solar panels were initially only used by people who wanted to live off the grid, but now they are a popular choice for homes and businesses across the UK. In recent years, there has also been an increase in solar farms, which is a further step in the right direction.
So exactly what kind of benefits are we talking about?
Low Reliance on Fossil Fuels
If we continue to use fossil fuels at our current rate, it is expected that we will deplete these resources by the year 2060. Before that happens, we need a sustainable source of energy that will not run out any time soon.
The sun provides a permanent alternative option and utilising solar power is the most effective and efficient way to generate energy. Taking advantage of this infinite resource by installing solar panels can lead to sustainable energy solutions as well as lower utility bills.
Decreased Dependence on National Grid
Most of us rely on the electricity grid to supply us with energy to power our homes. Because of this dependence, we are locked in to rising electricity prices every year and are exposed to power outages and breakdowns.
Thanks to solar panels, you can decrease your reliance on the national electricity grid. To enhance the efficiency of your solar panels, you can also make use of solar panel batteries to store excess energy for use at a later date when it is dark or when you need to boost your home’s energy intake.
Lower Water Consumption
Traditional energy generators consume many thousands of gallons of water every year. Water is used as a cooling agent for machines and processing fuels through pipes. Solar panels on the other hand, do not require any water at all to maintain optimum function.
Improved Air Quality
Most fossil fuels that are used to generate electricity are themselves toxic, such as methane, or they produce toxic by-products such as carbon monoxide. These fumes escape into the air and increase air pollution. This has an adverse effect on our health and air pollution has been linked to several diseases, including a wide range of respiratory issues and also some cancers.
By contrast, solar energy does not produce any harmful substances, making it a clean resource which benefits our health and the environment.
Slowing Down Climate Change
Installing solar panels is a simple and effective way of massively lowering carbon footprints. When fossil fuels are burned, the toxic gases released contribute to the greenhouse effect on our planet’s atmosphere. This results in the earth getting hotter more quickly than ever before.
If this trend continues, our planet will eventually be unable to sustain life. Increasingly extreme weather phenomena such as flooding, drought and heatwaves are all as a result of these greenhouse gases.
Solar power, on the other hand, does not release any emissions and does not contribute to global warming.
Monetary Incentives
After the initial installation cost, your solar panels will cost you virtually nothing. It can reduce your reliance on the electricity grid by up to 80%, creating a substantial saving on electric bills. But that’s not all.
Your solar panels generate excess electricity which can be sold back to the grid, which means you have an opportunity to earn money as well.
Is Solar Energy Sustainable?
Although we have some way to go before solar energy can be viewed as entirely sustainable, it is most certainly a much better alternative than fossil fuels that we are currently dependent upon.
Some challenges still need to be overcome. For example, minerals like nickel, copper, and cadmium, are necessary to make photovoltaic cells – and mining for these minerals can be very polluting. Nevertheless, there is no doubt that transitioning to solar power is an important and necessary move for the future of our planet.
With a climate crisis already upon us, there is a renewed focus on replacing our existing resources with cleaner and greener alternatives. Although installing solar panels is initially a relatively expensive decision, it provides many benefits in the long term. New technologies are also reducing the cost of solar panels, making them a more attractive option.
It’s important to find the right solar panel supplier and installer who can help you determine what type and size of solar panels are required to operate your home with optimal efficiency.
At Forever Green Energy, we pride ourselves in providing honest advice, a high quality job and excellent customer service. We install the latest solar panels and battery storage and can help you to maximize your cost savings and other benefits. To find out more, please feel free to contact us today