Feasibility assessment for deploying PV panels on tram tracks

New research from Poland has suggested installing 891 PV panels along the entire tram platform and inter-track spaces of four major transportation hubs. The analysis showed that the PV system could power all of the city’s tram stops, the passenger information system, and meet 10% of demand from service depots.

A researcher from Poland's Krakow University of Economics has analyzed the cost-effectiveness of installing PV panels in tram tracks of Krakow's Nowa Huta district.

“While PV integration in urban environments is not new, applying it specifically to tram track areas – with an analysis of technical feasibility, cost-effectiveness, and potential energy yield in a real urban setting – is novel,” author Tomasz Witko told pv magazine. “It addresses both the spatial limitations of dense cities and the growing need for decentralized renewable energy solutions.”

The oldest part of the district, which was at the center of the analysis, includes 38 tram stops and more than 13.5 km of double-track lines. It also hosts a tram depot, which services 185 trams daily.

The installations

The researcher has first identified key locations for possible PV installations, strategically located near large hubs, ensuring optimal sun exposure while using existing infrastructure. Namely, Plac Centralny im Ronalda Reagana hub which serves six tram lines; Rondo Czyżyńskie, which serves ten tram lines; Rondo Kocmyrzowskie which serves seven tram lines; and Kombinat which serves four tram lines. The analysis involved installing panels along the entire tram platform and inter-track spaces, in four to five spots at any hub.

The assumed solar modules for the analysis were the Longi LR5-66HIH 500W monocrystalline PV panels, due to their efficiency and durability. While each panel costs €390 ($456) when including the mounting structure, electrical components, labor, permits, and miscellaneous costs. Overall, the research calculated that 265 panels can be installed in Plac Centralny, 254 in Rondo Czyżyńskie, 183 in Rondo Kocmyrzowskie, and 189 in Kombinat. With a total of 891 panels across the four hubs, the estimated cost would reach €347,329.2.

“To assess the financial efficiency of the entire project, it is necessary to analyze the performance of PV panels and the potential amount of electricity they can generate annually,” explained the academic. “The analysis is based on data from laser scanning with a resolution of 0.5m. Based on this data, additional layers are created, serving as input layers for the model namely: slope and exposure. A value of 20% albedo was adopted for the entire area. The calculations assumed a lower efficiency than declared by the module manufacturer, 18% instead of 21.1%.”

The results

Based on data from the Kraków Balice climatological station for a typical meteorological year, Plac Centralny was calculated to have an annual electricity production of 120.61 MWh, Rondo Czyżyńskie of 116.61 MWh, Rondo Kocmyrzowskie of 93.58 MWh, and Kombinat of 87.41 MWh, for a total of 418.21 MWh. This would prevent the emission of 274.81 tons of CO2 annually and save around €75,000 in electricity costs. It is expected to account for 3.5% of the city's 12.5 GWh electricity demand for the tram system. That amount could power all stops, the passenger information system, and meet 10% of the demand from depots. The payback period was calculated at 4.15-14.2 years, depending on changes in energy prices and maintenance costs.

“One of the most unexpected outcomes was that despite the relatively small available surface area compared to conventional rooftop or ground-mounted installations, the calculated energy yield per square meter was highly competitive,” Witko concluded. “This is due to the unobstructed sunlight at tram stops and the optimized orientation of certain track sections. Furthermore, the payback period in some scenarios was shorter than initially anticipated, especially when factoring in the environmental benefits and avoided CO2 emissions.”

The research appeared in “Feasibility and cost-effectiveness of installing photovoltaic panels in tram tracks at major stops in Krakow's Nowa Huta district,” published in Renewable Energy.