Photovoltaics for businesses - it pays off. Case study of a PV micro-installation for the Terma company

In an era of galloping inflation and rising energy prices, more and more companies are choosing to invest in a photovoltaic installation. However, there are some companies that have decided to 'switch to the green side of power' much earlier. One example is Terma, which has been reaping the benefits of solar energy since 2019 and is using solutions from SolarEdge Technologies - a global leader in smart energy technology - to do so. Is it paying off for it? Of course!

 

• PV installation saves Terma around 40 000 PLN per year
• Reduction in grid electricity consumption by over 90 MWh in just 24 months
• Since the start of operation, a reduction in direct CO2 emissions of 137 tonnes
• Expected return on investment at current energy prices in less than 5 years

April 4, 2023 – TERMA is a Polish manufacturer of bathroom and decorative radiators, heaters, construction machinery and rehabilitation equipment. Since 1990, it has been serving people in more than 40 countries, on 4 continents. Terma has embedded its business in values that are the common denominator of all the processes it undertakes. The most important of these - innovation and economy - determined the investment in a photovoltaic micro-installation with an installed capacity of 49.68 kWp. on the roof of a building in Gdansk.

The 7,000 m2 building on which SunSol installed the PV system serves as an office and storage and production facility. Facilities of this kind are characterised by high energy consumption. The average monthly electricity consumption of the building is approximately 460 MWh, and the cost of purchasing this amount of energy is approximately 350,000 PLN. In Terma's case, the installed power was selected so as not to exceed the threshold of 50 kWp - the maximum permitted power of a micro-installation according to Polish regulations. This made it possible to carry out the construction and notification procedure for the micro-installation quickly and smoothly, without having to obtain connection conditions and a building permit. The investment was decided at the end of 2018 and the PV installation has been producing energy since the beginning of 2019.

"The ever-increasing costs of maintaining the building due to rising electricity prices led us to look for an innovative, yet safe solution to meet our needs. We decided to invest in solar energy and produce energy in our own micro-installation. The installation has proved very helpful to us, not only because of the reduction in operating costs, but also because of the security it provides us by charging our UPS system and ensuring that we always have backup power for our servers," says Bartosz Padoł, Photovoltaic Installation Implementation Supervisor at Terma sp. z o.o.

INSTALLATION COMPONENTS - HIGH QUALITY COMPONENTS

The investor wanted high-quality components that would provide smooth and safe operation of the PV system for many years. He decided on photovoltaic modules from the American manufacturer SunPower, which is at the top of the ranking of Tier 1 module manufacturers. 138 SunPower X22-360 COM modules were installed on the roof of the building, with a 25-year warranty. After the load-bearing capacity of the roof had been assessed by the constructor, a non-intrusive aero system was used to mount the PV modules, designed for east-west installations, whose impact on the load-bearing capacity of the roof can be considered negligible in principle. This solution is an alternative to a ballast system, the weight of which is significantly higher. The photovoltaic modules are inclined at an angle of approx. 10 degrees, which guarantees higher energy yield with an east-west orientation. This design solution provides additional protection to the PV system from the effects of violent atmospheric phenomena.

At the heart of the photovoltaic system is the inverter, which is the most decisive factor for the operating effects and safety of the installation. In the case of Terma's installation, this is a product from SolarEdge, a Global leader in smart energy technology, based on MLPE.

The installation is operated by two SolarEdge SE25K inverters, covered by a 12-year warranty, with SolarEdge P800 power optimisers in a 2:1 arrangement, i.e. two PV modules are connected to each power optimiser. This approach makes it possible to halve the number of power optimisers, while retaining all the benefits offered by optimising the system at module level. Terma's PV system supports 69 SolarEdge power optimisers, each with a 25-year warranty.

The technology used is equipped with a number of solutions to increase safety and reduce the risk of PV plant operation to a minimum. The built-in SafeDC™ function ensures that the voltage on the DC cables from the PV installation is reduced to a safe-to-touch level in the event of a grid failure or when the inverter is switched off. Rapid Shutdown technology, on the other hand, allows the cables to be quickly discharged to a safe voltage level within 30 seconds. Such technologies for the safety of PV installations are recommended by FM Global, among others.

With SolarEdge devices, Terma also has access to intelligent monitoring of the installation, allowing insight into the operation of each module. Smart solutions maximise system efficiency and reduce O&M costs.

Terma's installation was additionally equipped with an uninterruptible power supply system consisting of three BMZ model ESS 9.0 batteries and Victron Quattro 48/5000/70-100/100 chargers. Terma uses the PV system to power three UPS (uninterruptible power supply) systems designed to protect sensitive servers in the event of a power grid failure.

The installation of the PV system, thanks to SolarEdge's maximally simplified installation and commissioning procedure, took just a few days.

"Terma, as a manufacturer of premium heating systems and with high-end modern machinery, was only interested in top-class products that guaranteed both the highest yield and safety. These two parameters were met by Solaredge inverters. The photovoltaic system additionally powers a battery system that protects critical circuits in the factory. Already satisfied with the system's performance, Terma is planning to expand the installation" - says Michał Kitowski, president of SunSol.

BENEFITS FOR THE COMPANY AND THE ENVIRONMENT

Due to the high demand of the building, all the energy produced by the photovoltaic system is consumed on an ongoing basis. Such a scenario is beneficial from the perspective of the economics of the project, as it directly reduces the volume of energy that the company has to purchase from the energy retailer at increasingly higher rates. In addition, the reduced energy consumption from the grid translates into further savings for Terma related to the avoidance of fixed charges linked to the amount of energy consumed, such as the power charge.

Although the installed PV system does not cover the entirety of the building's huge electricity needs, it does bring the tangible benefits of producing its own clean, free and reliable energy generated from the sun. The photovoltaic installation for Terma has reduced the building's maintenance costs from day one, and the money invested is expected to pay for itself at current energy prices in less than five years.

The average annual productivity of the installation over its lifetime is 42.17 MWh of green energy. Each year of operation, the installation generates energy to the value of nearly PLN 40 000 and, in view of rising energy prices, these savings could increase significantly in the coming years.

In addition to the financial aspects, the PV installation also serves the environment. Since its inception, it has helped to reduce direct CO2 emissions by 137 tonnes! Each year, the avoidance of an average of 34 tonnes of carbon dioxide emissions also results in a reduction in the felling of 4,800 trees. That's as much as two hectares of forest!

"An in-house PV installation is undoubtedly an effective way to reduce property maintenance costs. In addition to these obvious financial benefits, the company also gains energy independence and builds an image as an environmentally conscious and responsible company. For small and medium-sized enterprises, we particularly recommend micro-installations, which are often the first step on a company's path to energy independence due to their ability to be implemented quickly and without requirements. This type of investment can be compared to securing cheap and clean electricity over a period of many years, which will at least partially help to make you independent of market price fluctuations," - comments Michał Marona, Country Manager at SolarEdge Poland.