How to increase the profitability of photovoltaics?

In recent years, there has been a growing trend of installing photovoltaic (PV) panels on homes. While it’s well-known that PV panels harness sunlight to generate electricity, there are several misconceptions surrounding their maintenance, operation, and profitability that need to be clarified.

Profitability of photovoltaics

In Poland, a typical photovoltaic setup generates around 1,000 kWh per year per 1 kWp installed. Given the current economic challenges like inflation and energy shortages, investing in photovoltaics is advantageous. Various incentives such as the Moj Prąd and Clean Air programs further boost the profitability of such installations. Typically, the investment pays off within 9 to 12 years.

The primary benefit of using energy from a photovoltaic system is self-consumption, where the electricity generated powers household appliances. This means you’re using what you produce, saving on purchased electricity. During self-consumption hours, you utilize energy from your photovoltaic setup without any additional cost.

Each unit of electricity consumed internally (self-consumption) saves you the cost of purchasing from the grid. As of April 2022, surplus electricity not used from your photovoltaic system can be sold back to the grid at the market price for that month. However, starting July 2024, the price for selling surplus energy will be based on the current hourly market rate, which may result in lower earnings for prosumers compared to the previous system.

Where to install photovoltaic panels?

Photovoltaic panels offer flexibility in installation, whether on the ground or on rooftops. For ground-mounted options, ensure a minimum 4-meter distance from the building foundation. When opting for ground installation, consider unobstructed space without shade from buildings or trees for optimal energy production.

Ground-mounted panels benefit from ample sunlight exposure and natural cooling, enhancing energy yield. However, if ground conditions aren’t suitable, rooftop installation is a viable alternative. South-facing roofs offer optimal sun exposure for energy production.

The angle of rooftop panels varies based on location, typically around 40 degrees for efficient energy generation. Choose the installation method that best suits your space and ensures maximum energy efficiency.

Sun exposure? impact on the profitability of photovoltaics

A common misconception about photovoltaic panels revolves around their performance in varying sunlight and temperature conditions. Contrary to belief, panels can still generate electricity on cloudy or winter days.

Modern panels are designed to operate effectively within a wide temperature range, from -40°C to +85°C. However, excessive heat can temporarily reduce efficiency, with a decrease of up to 10% in efficiency observed at temperatures above 25°C. In extreme cases, where temperatures on panel surfaces reach around 70°C, efficiency loss can be as high as 15%.

Ideal operating conditions involve sunlight intensity of up to 800 W/m2, an ambient temperature of 20°C (which corresponds to a cell heating temperature of 45°C), and a wind speed of 1 m/s. Standard testing is typically conducted at 25°C temperature and sunlight intensity of 1000 W/m2.

While PV panels perform exceptionally well on hot summer days, they can still harness solar energy even in cloudy conditions, albeit with reduced efficiency. Intense cloud cover may decrease efficiency by up to 90%, although such occurrences are infrequent and have minimal impact over extended periods. Ultimately, photovoltaic panels are reliable and operate year-round, dispelling the myth that they’re only effective in ideal weather conditions.

Snow removal and the profitability of a photovoltaic installation

It’s important to maintain your photovoltaic panels during the winter months as well. When snow covers the panels entirely, energy production can drop to zero because sunlight struggles to penetrate the snow layer.

Even when the sun is shining, the snow layer blocks photons from reaching the panel surface, limiting electricity generation. While small amounts of energy may be produced to power the inverter, significant electricity gains are hindered.

To address this, it’s advisable to gently clear the snow from the panels. Take care to avoid scratching the outer layer of the panels. Alternatively, for roofs with steep slopes, you can wait for the snow to naturally slide off. This ensures uninterrupted energy production during winter.

How do pollutants affect the profitability of photovoltaics?

Photovoltaic panels, whether mounted on rooftops or the ground, are exposed to pollution year-round. Dust, dirt, and other contaminants, such as bird droppings, can accumulate on the panels, reducing the surface area available for solar radiation absorption and consequently decreasing energy production.

When cleaning the panels, caution must be taken to avoid damaging them. Using a pressure washer, for example, poses a risk of damaging the seal between the glass and the aluminum frame, accelerating their degradation.

To address this issue, many companies offer cleaning services using advanced technologies like ion-cation systems and reverse osmosis. These methods can achieve purity levels of up to 99.9% and 95-98%, respectively.

Alternatively, rain provides a natural cleaning solution. For those willing to invest more upfront, some installations come with their own cleaning systems. These systems typically involve sprinklers connected to a tank containing cleaning fluid, ensuring automatic removal of impurities.

Innovative devices for washing photovoltaic panels

Entrepreneurs have been spurred by the rise of photovoltaic installations to develop and invest in technologies aimed at supporting the maintenance of PV panels. One such innovation is the Overmax X-Bee drone, designed specifically for cleaning panels in photovoltaic farms.

The drone is housed in a weather-resistant docking station situated near the panels. At scheduled intervals, the station opens, allowing the drone to take flight and commence its cleaning duties.

Overmax X-Bee drone; Source: technogadzet.pl

Equipped with LiDAR sensors and cameras for mapping the area, the device efficiently navigates the field and identifies panels. Once positioned over a panel, it sprays a specialized cleaning agent to remove dirt. After completing the cleaning process, it moves to the next panel, repeating the operation.

When the battery needs replacement or the cleaning liquid tank requires refilling, the device autonomously returns to the docking station.

Another innovation comes from Indian company Enray Solutions, which has developed a maintenance-free robot for cleaning PV panels. Powered by a built-in photovoltaic module and lithium battery, this robot doesn’t require an external power source. Instead of water, it uses brushes for cleaning, which are automatically cleaned when the device returns to the docking station.

Enray Solutions PV panel cleaning robot; Source: gadzetomania.pl

Constructed from lightweight yet durable aluminum, the robot ensures thorough cleaning without damaging the panels. According to the manufacturer, using the robot is 80% more cost-effective than traditional panel cleaning methods.

Furthermore, the device’s integration with the cloud enables remote control and monitoring by Enray Solutions. This functionality allows for real-time monitoring of the device’s operation and provides access to software updates as they become available.

Investment in photovoltaics and maintenance of PV panels

As photovoltaic panel installations gain popularity, owners are discovering the importance of proper care and management. Effective maintenance not only enhances energy efficiency but also prolongs the lifespan of the panels, resulting in increased returns for investors and prosumers alike.

Investing in a well-maintained and clean photovoltaic installation pays off quicker and ensures longevity of the modules. Proper utilization of photovoltaics offers a range of benefits, including:

• Reduced electricity bills over the long term
• Protection against rising energy costs
• Environmental stewardship by reducing reliance on traditional energy sources
• Incorporation of renewable energy into daily life

Beyond economic advantages, photovoltaics offer a sustainable alternative to conventional electricity generation methods. By harnessing solar energy, individuals can significantly lower their electricity bills over many years while minimizing environmental impact and pollution.

Is it worth investing in energy storage for a photovoltaic installation?

Excess energy generated by a photovoltaic installation can be effectively stored for later use, especially in off-grid island systems. In this setup, surplus energy not immediately consumed is stored in batteries to power the household during periods without sunlight, independent of the grid. Typically, these batteries support one charging and discharging cycle per day.

However, the cost of energy storage is significant, often reaching up to PLN 15,000, depending on battery capacity. To aid in financing, the Moje Prąd 5.0 program offers support for purchasing energy storage facilities with a minimum capacity of 2 kWh, covering up to 50% of eligible costs.

The key benefit lies in financial gain. Prosumers profit from the difference between the cost of purchasing electricity from the grid, including distribution fees, and the selling price of green energy back to the grid. Annual savings from using stored energy alone can total around PLN 3,000, allowing for the recovery of additional storage investment costs within approximately 5 years.

With an average battery warranty of 10 years and an operational lifespan of about 15 years, this solution ensures long-term energy independence and maximum utilization of renewable energy. By investing in a photovoltaic installation paired with energy storage, individuals not only reap financial rewards but also contribute to sustainable energy practices and enhance their energy independence.