Solar Panel Electricity Production

“How much electricity do solar panels produce?” is a question on the minds of many UK homeowners, business owners and property developers keen on adopting renewable energy.

With extensive knowledge in the solar panel and renewable energies industry, we’ll dive deep into how much electricity a solar panel can generate and help you better understand the ins and outs of technical industry jargon.

We’ll explore factors that influence solar panel efficiency, including their performance on cloudy days and the typical costs associated with installation.

While the initial investment in solar power can be costly, especially if you are not making use of energy grants like the ECO 4 scheme, the overall savings and environmental benefits are substantial.

Whether you’re considering solar panels for the first time or looking to optimise your current system, this informative guide aims to address and answer your concerns, so you can make a more informed decision.


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How Much Energy Do Solar Panels Produce For Your Home?

Average residential solar panels can generate between 250 and 400 watts (W) per hour from direct sunlight. Essentially, this means that a 400 W solar panel can produce about 1.75 kilowatts per hour (kWh) of electricity per day. Under optimal conditions, this equates to roughly 52.5 kWh of electricity per month.

Before we move on, let’s discuss the basics. It’s crucial to have a proper understanding of how solar panels work and the meaning of technical solar jargon:

  • A solar panel’s energy output is measured in watts.
  • All electrical items are calibrated in watts and use alternative current (AC) to function.
  • The higher the solar panel wattage is, the more power it generates.
  • 1,000 watts = 1 kilowatt (kW).
  • A kW is a unit of power that represents the rate at which energy is used or produced.
  • Kilowatt hours (kWh) is a unit of power that represents the amount of energy consumed or produced over a given period. For instance, if a 1kW appliance runs for 2 hours, it would have consumed 2 kWh of energy.
  • “Peak sun hours” refer to the amount of usable sunlight a solar panel can extract from the sun.
  • “Solar” refers to the energy from the sun.
  • Solar panels generate energy through the photovoltaic (PV) process. Hundreds of PV cells make up a solar panel.
  • Solar power is produced when PV cells are exposed to sunlight, generating direct current (DC).
  • DC electricity is converted into alternating current (AC) which is used to power our homes.

Now that we’ve got the basics out the way, let’s continue with how much energy solar panels can produce.

A solar panel’s energy production varies based on several factors, such as:

  • Model
  • Size
  • Efficiency
  • The amount of sunlight each panel receives
  • The number of panels you have in total

For instance, a 350 W solar panel in the UK can generate up to 265 kWh of electricity per year. If a home or business owner has a 12-grid system, the solar panel production would equal roughly 3,180 kWh of electricity per year.

To put this into perspective: According to Ofgem, the UK’s energy regulator, an average 2- to 3-bedroom home uses approximately 3,800 kWh of electricity per year. This would roughly cost you around £900 – £1,200 in electricity charges annually.

While these energy consumption figures are based on lifestyle routines and usage patterns, they indicate how much money one can save when moving over to solar power.

Furthermore, the Energy Savings Trust suggests that a typical UK home with a 4.2 kW solar panel system can shave off between £210 and £510 on their annual energy bills. Solar panels have the potential to reduce electricity costs by 15% – 20%.


How Do I Calculate A Solar Panel’s Output?

If you want to calculate how much power output your solar panels are generating, here is a formula that would be helpful to use:

  • Power in watts (W) x average hours of direct sunlight (peak sun hours) = daily watts per hour
  • Divide the daily watts per hour by 1,000 = kWh

Example: You have a 350 W panel that receives 6 hours of sunlight per day:

  • 350 W x 6 = 2,100 Wh
  • 2,100 / 1,000 = 1.2 kWh per day

Once you have mastered this simple formula, it’s easy to calculate your solar panel production per week, month, or year.

Solar Panels Country Home

How Many Watts Does A Solar Panel Produce?

Solar panel wattage indicates how much DC power it can produce under ideal conditions. As mentioned, an average solar panel has a power rating of around 250 – 400 watts. It’s worth mentioning that these are estimates. External factors, such as temperature variations or obstructions, can impact the true output value.

You may find that your solar panel system has 245 W or 345 W next to the name on each panel. These numbers indicate the wattage each panel generates.

For a grid-tied solar panel system, this may not be a significant factor to consider as these systems rely on energy generation directly from the grid. However, if you are off the grid or use a battery storage system, understanding your solar panel system wattage is important.

For instance, a solar panel system in Glasgow may generate more power (i.e. more wattage) than a solar system in the Scottish Highlands because of the amount of sunlight each region receives.

Side note: Solar panel production is reduced by about 83% during winter in the UK.

Solar Panels Edinburgh

How Effective Are Solar Panels?

The effectiveness of solar panel systems is determined by how well they convert sunlight into electricity. There are three variations used for residential solar panels, such as:

  1. Monocrystalline solar panels – these highly efficient solar systems are more costly when compared to others on our list. They are made from pure silicon, perform better in shady areas, and often outlast other types.
  2. Polycrystalline solar panels – these are easier on the wallet when compared to monocrystalline types. They are made from fused silicon crystals and offer decent efficiency.
  3. Thin-film solar panels – these are the cheapest option. They offer the least amount of power output and have a shorter life span.

To understand how effective solar panels are, let’s take a look at the statistics below:

  • In 2021, Scotland’s electricity production released approximately 26.9 grams of carbon dioxide per kilowatt hour into the atmosphere (gCO2e / kWh). This is in line with the government’s 2018 Climate Change Plan of below 50g CO2 per kilowatt hour.
  • According to the Microgeneration Certificate Scheme (MCS), roughly 142,000 Scottish homes already have solar panels installed. That’s a 30% increase when compared to last year (2022).
  • Between January and March 2023, Scotland generated 10.3 terawatts per hour (TWh) of renewable electricity (that’s equal to 10.3 billion kWh).

These statistics show how effective solar panels can be and are paving the way for a greener tomorrow.

Investing in a solar system can be expensive, with a typical 5 kW solar panel installation costing in the range of £6,000 – £7,000. But, with the proper care and maintenance, these systems can last for up to 25 years! Solar panel installations are becoming the preferred renewable energy source, with many government-backed schemes available at your disposal.

Can I Store The Electricity My Panels Generate?

Yes, you can store surplus solar power.

“Off-the-grid” solar panel systems are solar panel systems that do not rely on the grid for their energy. They can store surplus (excess) electricity for later use. A solar battery, also referred to as a solar energy storage system, is a device that stores this extra energy.

Solar panels, especially on sunny days, can generate more power than the average household can use within a day. This is where solar battery units come into play. These valuable additions connect to the solar panels and capture and store surplus energy in the batteries. This additional power is also used to charge the storage unit.

Not only do solar panel storage systems increase your home or business’s energy efficiency but they are brilliant to have if you want to become more self-reliant.

How Do I Check That My Solar Panels Are Working Efficiently?

Ensuring solar panel efficiency is vital to your home or business’s energy needs. You need to check how much power they are generating constantly. This includes:

  • Monitoring the system: Most solar-powered systems come with built-in monitoring tools – such as digital meters – to track real-time energy production.
  • Checking energy bills: A significant reduction in electricity bills indicates that your solar system is working at optimal efficiency. If not, there may be a problem.
  • Inspecting: Regularly inspect the physical appearance of your solar panels. Physical dirt or damage can reduce their efficiency.
  • Professional advice: Periodically (e.g. once a year) have your system checked by solar panel technicians or professionals. They are trained to access the system’s overall performance. Do not try to fix any damages or problems yourself.
solar panels small town Scotland

Are There Grants For Solar Panels In Scotland?

Much like us humans, solar battery storage systems age with time. On average, a solar battery system can last up to 10 years, depending on usage and maintenance. In a lot of cases, a high-quality solar battery storage system can function for up to 25 years.

But here’s something that you should know: the battery’s depth of discharge plays a significant role. It refers to how much of the battery’s energy is used up before it’s recharged. The less you drain your battery, the longer it’ll last.

While we’re on the topic, it’s worth noting that solar panels typically outlive their batteries. Generally, solar panel systems have a lifespan of around 25 to 30 years. So, this is something you should factor in when choosing a battery. Luckily, most solar battery storage systems come with a 10-year warranty.

Are There Grants For Solar Panels In Scotland?

Yes, there are funding grants and loans available for eligible Scottish households. Envirohomes Renewables has expertise in the industry and is committed to advising individuals about their energy rights. Eligible customers can access a range of home improvement solutions via government-backed schemes, including free solar incentives and solar panel installations.

ECO 4 scheme

The ECO 4 scheme is the fourth instalment of the UK government’s initiative and is due to run until March 2026. This scheme aims to reduce fuel poverty across UK and Scottish homes. It focuses on improving heating systems and reducing energy costs. This includes the installation of renewable energy sources such as solar panels.

This is one way the Scottish government aims to reach its ambitious plan of having net-zero carbon emissions by 2045 – five years earlier than the rest of the UK. Solar panel systems are available to eligible households when the option of heat pumps or biomass boilers has been ruled out.

Free solar panels are available to:

  • Homeowners or private tenants
  • Households with a poor Energy Performance Certificate (EPC) rating of D or lower
  • Individuals who earn less than £19,720 per year
  • Individuals on benefits (e.g. Child Support, Income Support, Disability Grants, etc.)
  • Pensioners, over the age of 60, who receive Pension Benefits

The ECO 4 Scheme is not only restricted to solar panel installations. It can also be used for the following home improvements:

  • Various insulations (such as loft and cavity wall insulation)
  • Upgrading heating systems (e.g. heat pumps, central heating)
  • Boiler upgrades and boiler replacements
  • Renewable energy supply, such as solar panels and solar storage units


Solar panel output means how much electricity your solar panels generate under optimal conditions. Power output is measured in two ways: watts (W) measure the instant power output rating and kilowatts (kW) measure the accumulated power output over some time.

No, solar panels work differently in different weather conditions. For example, in summer, solar panels are exposed to more direct sunlight, resulting in more energy production over a longer period (i.e. peak sun hours). In winter or under cloudy conditions, solar panels receive less solar energy from the sun, therefore generating a lower power output.

Yes. Despite the often cold and cloudy weather, solar panels work well in Scotland.

A 5 kW solar system installation – which generates roughly 4,500 kWh of electricity per year – will cost around £6,000 – £7,000. This figure can vary based on the number of panels required, building design, and location – among others.

It is possible to solely rely on solar-powered systems; however, you need to consider several factors. Such as:

  • The size of the solar system
  • The amount of power output it can produce
  • The location or area of where you live (e.g. Edinburgh vs Inverness)
  • Your daily peak sun hours (i.e. how much sunlight the unit receives)
  • Your average household energy consumption

An average residential solar system can generate between 250 and 400 watts per hour from direct sunlight. The amount of power or electricity that a solar panel can produce is determined by how much sunlight it can convert into electricity.

High-efficiency systems, such as monocrystalline solar panels, can produce more electricity when compared to cheaper models, like thin-film solar panels, on the market.

Final Thoughts

As we wrap up this comprehensive guide, it’s clear that the world of solar panels offers immense potential for those willing to navigate its complexities. From understanding solar panel output capacities to calculating power wattage and government grants, there are plenty of opportunities for savings and sustainability.

For all homeowners, business owners, and property developers out there, remember that every solar panel installed is a step towards a more sustainable, greener and cost-effective future. Installing solar panels also helps Scotland to reach its ambitious plan of net-zero emissions by 2045.

Drawing from a wealth of industry knowledge, you can now feel more empowered to make informed decisions in your renewable energy plans. The message is clear: the future is solar.

For help with your ECO 4 Scheme applications and checking your eligibility, speak with the team from Envirohomes Renewables today!