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Solar Thermal

City Plumbing offers a diverse selection of solar thermal products, all designed to help you make an effortless transition to renewable technology. Providing a comprehensive selection of essentials, from panels to pipes, mounting to accessories, City Plumbing has all your solar thermal needs covered.
What Is Solar Thermal?
Solar thermal is a category of technology that harnesses the sun's heat to generate thermal energy. Unlike photovoltaic (PV) technology, which converts sunlight directly into electricity, solar thermal systems utilise mirrors or collectors to absorb and concentrate solar radiation, heating a fluid such as water or oil. This heated fluid can then be used for various purposes, including:
  • Heating water and spaces: This is the most common residential and commercial application, where solar thermal collectors are used to provide hot water for homes, schools, and businesses.
  • Industrial processes: Solar thermal can provide high-temperature heat for a wide range of industrial applications, such as desalination, food processing, and chemical production.
  • Electricity generation: In large-scale power plants, concentrated solar power (CSP) systems use mirrors to focus sunlight onto a receiver to produce steam, which then drives a turbine to generate electricity.
Why Choose Solar Thermal?
​Reduce Hot Water Bills
Solar thermal systems can significantly reduce your hot water bills. On average, a well-installed system can lower your water heating costs by 50% to 80%. The exact savings depend on factors like your location, how much hot water you use, and the efficiency of your system. While a solar thermal system alone may not cover 100% of your hot water needs, especially during winter months, it can provide up to 90% of your hot water in the summer.
Eco-Friendly
Solar thermal energy is a low-carbon renewable energy source that helps you reduce your carbon footprint. By using the sun's heat to produce hot water, it replaces the need for fossil fuels like natural gas or oil. Using solar thermal panels produces approximately 44 gCO2e/kWh of carbon emissions, which is significantly less than the 418 gCO2e/kWh produced by a gas-fired power plant.
Works With Modern Heating Systems & Long Lifespan
Solar thermal systems are designed to be integrated with most modern heating systems, making them relatively easy to install without requiring a complete overhaul of your existing setup. These systems also have a long lifespan, typically lasting 20 to 25 years, providing a long-term investment.
Adds Value to Your Home
Installing solar thermal panels can increase the value of your home. It can also improve your Energy Performance Certificate (EPC) score, which is a key indicator of a property's energy efficiency. A higher EPC rating makes a home more attractive to potential buyers or renters. Studies show that a property's value can increase by an average of £9,003 when moving from a D to a C rating, a jump that can often be achieved by installing solar panels. Some studies estimate that solar panels can add an average of 14% to a home's value.
How Does Solar Thermal Work?
A solar thermal system is a type of renewable energy technology that uses the sun's heat to provide hot water for a home. Unlike solar PV panels, which generate electricity, solar thermal collectors heat a fluid that in turn heats your water supply.
How it Works
A solar thermal system is relatively simple in its design and function. The process involves a few key steps:
  1. Collection: Solar collectors, typically mounted on a roof, absorb solar radiation. Inside these collectors, a special fluid (often a mix of water and antifreeze) is heated by the sun's energy.
  2. Circulation: A small pump circulates this heated fluid from the collectors down to a hot water cylinder inside your home.
  3. Heat Exchange: The fluid passes through a coil, or heat exchanger, inside the cylinder, transferring its heat to the cold water stored in the tank.
  4. Distribution: The newly heated water is then ready to be used for taps, showers, and other hot water needs. The cooled fluid is pumped back to the collectors on the roof to be reheated, repeating the cycle.
Solar Thermal vs. Traditional Heating Systems
The fundamental difference between solar thermal and traditional heating systems lies in their energy source and how they generate heat.
  • Energy Source: A solar thermal system uses free and renewable energy from the sun. In contrast, a traditional heating system relies on fossil fuels like natural gas or oil, or on electricity from the grid.
  • Environmental Impact: Solar thermal systems have very low carbon emissions, making them an eco-friendly option. Traditional heating systems, which burn fossil fuels, result in high carbon emissions.
  • Running Costs: Running costs for solar thermal are extremely low since sunlight is free. Traditional heating systems can have high running costs that are subject to fluctuating energy prices.
  • Primary Function: The main purpose of a solar thermal system is to produce hot water for domestic use. A traditional heating system typically produces both hot water and space heating, such as a central heating system.
Backup Heating
A key component of a solar thermal system is the backup heater, which is essential for ensuring a consistent supply of hot water, especially in the following scenarios:
  • During cloudy or rainy weather: When there isn't enough sunlight to heat the water to the desired temperature.
  • In winter: The system's performance naturally decreases during colder, shorter days.
  • When hot water demand is high: If you use more hot water than the system can produce on a given day, the backup heater will kick in.
The solar thermal system is connected to a conventional boiler or immersion heater that acts as a backup. The system first uses solar energy to pre-heat the water. The boiler or immersion heater then only needs to "top up" the temperature to the required level, significantly reducing its workload and the amount of energy it consumes.
Common Questions About Solar Thermal Installation ​
What Is the Solar Thermal Installation Process?
A solar thermal system installation is a straightforward process that typically takes one to three days for a standard residential property. While the upfront cost and reliance on sunlight may be concerns, the long-term benefits in energy savings and environmental impact make it a worthwhile investment.
The installation involves two main parts: the outdoor collector and the indoor components.
  1. Roof Assessment: An installer first assesses your roof's suitability, checking for a south-facing orientation and sufficient, unshaded space.
  2. Panel Installation: The solar collectors are mounted onto the roof. This process involves securing mounting frames to the roof rafters and then attaching the collectors.
  3. Indoor System: Inside your home, a new hot water cylinder with a dedicated solar coil is installed. A small pump station and a controller are also fitted, often in the loft or near the cylinder.
  4. Plumbing and Wiring: The system's pipes are run from the roof collectors to the new hot water cylinder. The fluid (a mix of water and antifreeze) is then added, and the system is pressurised and connected to your existing hot water pipes.
  5. Commissioning: The installer tests the system to ensure it's functioning correctly and provides you with instructions on how to use and monitor it.
Addressing Key Concerns About Solar Thermal
While solar thermal is an excellent technology, it's important to be aware of a few common concerns.
  • Initial Cost: A typical solar thermal system can cost between £3,000 and £5,000. This can be a significant upfront investment, but it's a one-time expense that pays for itself over time through reduced energy bills.
  • Performance in UK Weather: It's a misconception that solar thermal systems don't work in the UK. They can still generate heat on cloudy days, and while their efficiency drops in winter, a well-designed system can provide 25% of your hot water in winter and up to 90% in summer. The system is always supported by a backup heater (your boiler or immersion heater) to ensure you have hot water on demand.
  • Maintenance: Solar thermal systems require minimal maintenance, usually just a yearly check-up to ensure optimal performance.
Is Solar Thermal Worth It?
Despite the initial cost, the benefits of installing a solar thermal system are substantial and long-lasting.
  • Significant Bill Savings: A system can reduce your hot water bills by 50% to 80%, leading to substantial savings over its 20-25 year lifespan. For a typical household, this can amount to savings of hundreds of pounds a year.
  • Increased Home Value: A solar thermal system can improve your property's Energy Performance Certificate (EPC) score, making it more attractive to potential buyers and increasing its market value.
  • Environmental Impact: By using a clean, renewable energy source, you can significantly reduce your home's carbon footprint. A typical system can save around 375kg of CO2 per year compared to a gas boiler.

What Types of Solar Thermal Does City Plumbing Sell?

City Plumbing sells solar thermal products, including solar thermal panels, pipes, packages, mounting, and accessories. With industry-leading brands such as Grant, Solfex, Worcester Bosch, Armacell, Altecnic, and many more, we’ve got a solar thermal product to suit all your requirements.

Buy Solar Thermal at City Plumbing

City Plumbing remains the first choice of local plumbers’ merchants for all homeowners and installers working in the trade.​
With a high Trustpilot rating that we’re extremely proud of, a staggering amount of knowledge from four-plus decades of experience, and some of the most outstanding plumbing and heating products and advice, we’re here to ensure you can get the job done.​
Offering you access to over 350 branches nationwide, our prices continue to remain the most competitive to further ensure you get all your projects finished on budget.
​With several Delivery Options and a Click & Collect service, if you’re looking for a City Plumbing near me, type your postcode into our branch locator to find your nearest City Plumbing Supplies.

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