We're launching a new series #MONDAYWITHEXPERT, in which we'll dispel your doubts on topics related to construction and interior design. In today's article, we discuss photovoltaics with Maciej Drobczyk of IBC SOLAR Poland.
Maciej Drobczyk - Expert in the design of photovoltaic installations, taking into account the benefits in the long and short term, specialist in the safety of PV installations, available forms of subsidies for PV investments for prosumers and companies, and the selection of appropriate PV solutions depending on the assessment of roof eligibility, and environmental conditions. At IBC SOLAR Poland he assumes the position of Country Manager, working with business customers, providing training on the proprietary PV Manager installation design software, and providing substantive support to installers and partners. Expert of the content initiative "photovoltaics on flat roofs" of the DAFA association.
Properly selected installation always pays off
© IBC SOLAR Poland
What kind of changes have occurred in the billing of energy produced and are they beneficial for the recipient?
Maciej Drobczyk: The entry into force of the amendment to the RES Act on April 1, 2022 has introduced quite significant changes in the settlement of energy produced. Those who set up a photovoltaic installation after March 31 are subject to net-billing. What does this mean? In this case, electricity will not be given and received as before, but will be sold and bought from the operator according to certain rates. On the other hand, those who had their own PV installation even before the amendment came into effect, that is, before March 31, 2022, can use the previous rules, the so-called net-metering, for the next 15 years.
Due to the changes, the discount system, which is metrically billed in kilowatt-hours (net-metering), has been replaced by a new one involving monetary billing in PLN (net-billing).
Under the new form of billing, surplus energy produced is sold to the grid, while the missing energy must be purchased from the supplier. Fortunately, this has not discouraged would-be prosumers from buying photovoltaic panels, but has inspired them to invest in comprehensive solutions. Increasingly, our customers are choosing to expand their PV installation with a heat pump or energy storage. All this to make the most of green energy in their homes and not be fully dependent on the electricity supplier.
How much does it cost to set up photovoltaics in a single-family home in 2023?
Maciej: Each photovoltaic installation project is created with the individual needs of the future prosumer in mind. That's why it's so important to properly match the size of the system to the energy needs for a given household, which in turn translates into what costs will have to be incurred in a given case. It is worth noting that many factors influence the final price. I mean, for example, the size of the system and the components selected, the experience and knowledge of the installer or even the region of Poland where the installation is built. It is assumed that the average cost we have to pay for 1 kWp of installation is about PLN 5,000.
It is worth emphasizing that this is only a base amount. Therefore, we must approach the subject comprehensively and analyze the entire cost estimate even before deciding to install photovoltaics. The fact that the investment itself is expensive, but the benefits of green energy are so many that it pays to install PV modules on the farm. In addition, thanks to the available rebates and subsidies for the installation, we can not only save, but also increase the value of the property.
How to get a subsidy for photovoltaics?
Maciej: Currently, we can take advantage of several government programs, such as Mój Prąd, which includes subsidies for PV installations for individuals and businesses, as well as for single-person households; Czyste Powietrze, which applies to subsidies for, among other things, replacing heat sources, installing solar collectors and heat pumps; and Prosument, which includes subsidies for renewable energy systems. This year's fifth edition of the Mój Prąd program also introduced a subsidy for the installation of heat pumps and solar thermal collectors for hot water heating, so we can get even more support for a newly installed photovoltaic system.
In order to join the program, there are several steps to follow, including preparing the necessary documentation and then applying for the subsidy. When choosing a photovoltaic supplier, it is good to bet on the one who will guide us through this demanding process. Then we have a guarantee that we will not skip anything and will provide a set of required materials, and the installation itself will be installed correctly.
We can use the energy obtained from photovoltaic panels to heat water
© IBC SOLAR Poland
When is photovoltaics not paying off?
Maciej: A properly sized installation will always pay off. A properly designed PV installation will guarantee high performance of the energy produced, which in turn will translate into faster payback. As an example, let's discuss two different methods of calculating the profitability of such an investment.
The first method assumes that 1 kWp (kilowatt-hours) of PV installation costs PLN 5,000, and that the performance of the system allows to generate about 1,000 kWh (kilowatt-hours) of electricity per year. Assuming that the installation will operate for 15 years, the total amount of energy generated will be 15,000 kWh. Given current prices, the value of this generated energy is equivalent to PLN 15,000. With a household consuming 4,000 kWh per year, a 5 kWp installation - which costs PLN 25,000 - will be able to generate 5,000 kWh of electricity per year. Assuming that we will be able to use half of this energy on an ongoing basis, electricity bills will decrease by about PLN 2,500 per year, which will reduce the payback time of the investment to about 10 years. In addition, the ability to sell surplus energy to the grid allows us to get an additional profit of about PLN 1,000 per year. Thus, the use of a 5 kWp installation is able to pay back the cost of the investment in about 7 years, and with the inclusion of subsidies and tax credits, this time can be reduced even to 5 years.
The second method of calculation assumes that 1 kWp of photovoltaic installation costs PLN 5,000, and the installation will operate for 20 years, generating a total of 20,000 kWh of electricity. At the same time, we can determine that the cost of 1 kWh purchased from the supplier is in the range of a PLN 1, and the cost of 1 kWh of energy produced from the photovoltaic installation is PLN 0.25 (based on the cost of the installation and the amount of energy produced during its 20-year operation). Assuming module degradation and lower yields in subsequent years, we are still within the average price of PLN 0.30 per 1 kWh. The value of the savings generated by 1 kWh of energy produced by the installation is therefore PLN 0.70. In addition, each 1 kWh given back to the grid pays for itself, as the selling price of energy varies between PLN 0.30 and PLN 0.50. Ultimately, assuming self-consumption of 50%, 1 kWp of photovoltaic installation generates about PLN 350 in savings (PLN 0.70 x 500 kWh) and about PLN 150 in profit from energy sales (PLN 0.30 x 500 kWh), for a total of about PLN 500 each year. Thus, at current energy prices, the payback time is 10 years.
You can benefit from photovoltaics even if you live in an apartment building
© IBC SOLAR Poland
Is it possible to heat water using photovoltaics?
Maciej: As much as possible, we can use the energy obtained from photovoltaic panels to heat water in our household. There are heaters available for sale, which we run thanks to a timer controller when the PV system generates electricity. There are also more developed systems that automatically allocate the overproduced energy to heat hot water. In a similar "smart" way, we can combine a heat pump with a PV system and heat water when we have energy from the sun. Interestingly, this type of solution, based on a home energy management system (HEMS), is covered by additional funding from the government's Mój Prąd program.
How do you heat your home with photovoltaics?
Maciej: As with heating water through a PV system, there are now several solutions we can use to heat our house. The simpler ones involve installing an electric boiler or heater that uses the energy produced by photovoltaics to heat central heating or DHW water. Another possible solution is the installation of heating mats, controlled fully intelligently on the principles of HEMS energy management - similar to the use of heaters. However, one of the most common options is the installation of a heat pump. We can then, in a more or less advanced way, combine this device with a PV installation, which will translate into maximum use of the surplus energy produced from the sun.
The photovoltaic installation cleans up on its own
© IBC SOLAR Poland
Is it possible to install photovoltaics on a balcony?
Maciej: Of course, it is possible to install photovoltaic panels on a balcony. Interestingly, there are even ready-to-assemble kits available for sale. In such a situation, we need to use the help of a person with the appropriate authorizations, who will connect such a PV installation to the home grid and complete all the formalities. However, it is important to remember to always choose products from proven manufacturers. Then we can be sure that the panels are made of high-quality components, which will translate into their daily functioning.
Due to the small areas of balconies, the power of the installation will not be too high, so the unit cost of installation will be relatively higher than with large PV systems. Nevertheless, observing the current situation in the real estate market, including the number of apartments and available balconies, and, above all, the growing demand for such solutions, more and more companies are choosing to introduce this type of service into their offert.
How do you keep photovoltaics clean?
Maciej: By definition, a photovoltaic installation cleans itself and you don't need to interfere in this process. This is affected by the way the panels are arranged, or more precisely, their installation at a certain angle, which is usually more than 5 degrees, so that some of the dirt simply falls to the ground. Additional factors that affect the self-cleaning of the modules are a special hydrophobic coating that reduces the adhesion of dirt, as well as precipitation, as it effectively removes accumulated dirt, including pollen and dust.
However, when you decide to wash the panels yourself, there are a few rules to keep in mind. It is not advisable to clean the PV system when the panels are hot, so try to choose times of the day when the sun does not shine too much. In addition, we should avoid sharp objects and aggressive chemicals, and use only demineralized water for rinsing. Every time we wash the modules, the hydrophobic layer can be damaged or disappear, which can result in worse water drainage. However, if we see the need to clean our PV installation, we can use the help of specialists. There are companies on the market that offer such services.