A Chinese research group has created a new method to calculate PV potential on the roof on the roof, not only on the basis of roof areas, but also including installation parameters and economic feasibility. The new methodology was demonstrated in Nanjing, East -China, and turned out to be superior to conventional methods when it comes to estimating the planned capacity.
Researchers from the Chinese Nanjing University of Information Science and Technology have proposed a new method for estimating potential in the field of solar energy on the roof on an urban scale. Although traditional methods focus their calculation extensively on the available roof area, the proposed technology is based on installation parameters and economic feasibility.
“The method assesses the economic feasibility of roof areas that are suitable for the installation of a PV panel on solar PV due to the required energy demand and payback period and calculates the potential of the solar PV power generation of urban roofs based on the placement of Solar panels, “the team explained. “Few studies have considered the actual installation layout of PV panels of solar energy in the potential assessments on the roof of Zonne-PV on the city scale.”
The proposed method consists of four steps. Firstly, an empirical model based on the sun of the sunshine 3D data uses to calculate solar radiation when building roofs. The second step takes into account the ideal PV panel arrangement, whereby the minimum boundary corner of each roof is calculated. Subsequently, a greedy algorithm from earlier scientific literature is used to fit as many panels as possible, so that obstacles are avoided. Safety margins near roof edges are also considered.
In the third step, the method calculates a threshold for the minimum solar radiation needed to make solar panels economically viable. The parameters of the calculation include installation costs, payback time, the share of the electricity that is sold to the schedule, feed-in rate, electricity price, panel surface and panel efficiency. The fourth and final step compares whether the solar radiation is received by each PV panel from the sun is larger than the threshold of the solar radiation.
“Solar PV panels with average solar radiation smaller than the calculated threshold are excluded,” the group said. “This process yields the final PV panel setup on solar energy and the corresponding solar radiation. Subsequently, the module efficiency of the solar -PV panels is used to calculate the potential distribution of PV current generation on the roof. “
A case study to show that the new technology was being carried out in the city of Nanjing, in East -China. Various teledetation data, vector data and meteorological parameters come from sources such as the Autonavi card, the digital height model (DEM), NASA and the Nanjing Meteorological Bureau. The LR5-72HPH-550 M module from Longi was used as a reference for price, size and efficiency data.
“We calculate the threshold of the solar radiation by setting the payback time at 10 years to ensure that most PV panel locations are economically viable,” the scientists added. “The Electricity Scenario parameter is set to 1, which means that all solar -PV current generation is sold. The fully on-grid distributed electricity price is CNY 0.49/kWh ($ 0.07/kWh) in Nanjing. The costs of one Solar PV panel are CNY 672 ($ 94.8). The module efficiency is 21.3%. “
According to the results of the new method, the available roof area for PV in Nanjing is 122 km2, with 28.87 TWH electricity potential every year. These results could meet 39.85% of the city’s electricity demand in 2022, which was 72.45 TWH. Compared to the traditional estimation method for solar PV potential estimates, the new technology prevents the generation potential to overestimate per unit area by 13.08%.
The new tool was introduced in “Evaluation of the photovoltaic potential of solar energy of buildings based on the installation parameters of photovoltaic modules“Published in Solar energy.
This content is protected by copyright and may not be reused. If you want to work with us and reuse part of our content, please contact: editors@pv-magazine.com.
