By Ts. Dr. Salmia Beddu
Have you ever wondered if you could power your household appliances using electricity sourced naturally? And not just any electricity, but sustainable energy?
Imagine a scenario where the energy powering your home is generated from the roads right in front of it. Moreover, imagine if the streetlights and traffic lights could also be powered by the same source. How can this become a reality?
Malaysia, with its tropical warm climate, is one of the Asian countries where this vision could be realised. Situated entirely in the equatorial region, Malaysia experiences temperatures ranging from 21 to 35 degrees Celsius. Additionally, asphalt pavement, commonly used on roads, can absorb a substantial amount of heat during the summer season, heating up to 70 degrees Celsius. Interestingly, this retained heat in the asphalt pavement can continue to provide energy even after sunset, unlike traditional solar cells. Considering its excellent heat-absorbing properties and wide use in parking lots, tarmacs, and roadways, harvesting thermal energy from asphalt pavement using solar collectors holds great promise.
Immense potential to harness solar power
The Malaysian Road Statistics 2021 by the Public Works Department (JKR) revealed that the total length of federal roads is 20,017.97 km, while state roads cover 247,027.61 km, resulting in a grand total of 290,099.38 km. These figures exclude the local and rural roads under local government authority. With such an extensive road network combined with Malaysia’s warm climate, the country has immense potential to harness solar power as a renewable energy resource.
Solar roadways are an emerging technology that can generate electricity and provide power to transportation infrastructures and facilities. They offer an effective solution to mitigate the heat island effect and environmental pollution, essentially transforming pavements into new ‘energy farms’.
The advancement of technology, economies of scale, intensified competition, and other factors have led to exponential growth in photovoltaic power generation since 1992. Photovoltaics have evolved into a mainstream power source, with a significant reduction in the price of photovoltaic modules. This reduction has brought about grid parity in numerous locations worldwide, indirectly fostering the development of solar roadways.
Profit, people and planet
Finding cost-effective alternatives for renewable energy sources aligns with the principles of sustainability, which consist of three pillars: economic, social, and environmental. These principles are often referred to as profit, people and planet.
At the national level, Malaysia, in conjunction with the implementation of the National Green Technology Policy in 2009, is actively pursuing green technology initiatives and programmes.
Tenaga Nasional Berhad (TNB), the sole energy distribution company in Malaysia, aims to reduce its carbon footprint while promoting environmental sustainability.
On a global scale, UNESCO has introduced the 17 Sustainable Development Goals (SDGs) to foster prosperity and protect the planet. These goals recognise that eradicating poverty must be coupled with strategies for economic growth, addressing social needs such as education, health, social protection, and job opportunities, while also tackling climate change and environmental protection.
Development of solar roadways
Several other countries, including China, France, and the Netherlands, have made significant strides in the development of solar roadways.
In late 2017, China inaugurated a 1km solar highway in Jinan, the capital of Shandong province. Spanning 5,875 square metres, this solar highway can generate up to 1GWh of electricity annually, enough to power 800 homes! The Chinese government plans to utilise this electricity to power streetlights, billboards, CCTV cameras, and even heat the road surface to melt accumulated snow. Within its first 14 weeks of operation, the road generated 96MW of energy.
Similarly, France has opened a 1km solar roadway in Normandy. Constructed by Colas, a prominent Anglo-French construction company, this solar roadway spans 2,800 square metres of photovoltaic cells. It is estimated to generate sufficient energy to power streetlights in the nearby village, which is home to approximately 3,400 people.
The Netherlands has also implemented an energy-harvesting bike path paved with glass-coated solar panels. After one year, the SolaRoad solar-panelled bike path generated an impressive 70 kilowatt-hours per square metre, exceeding the designers’ expectations and providing enough power for approximately three houses.
Overall, the application of energy harvesting from roadways holds tremendous potential within the energy harvesting industry. Stakeholders such as TNB, Lembaga Lebuhraya Malaysia, JKR, and research institutes like the Institute of Energy Infrastructure (IEI) in UNITEN can play vital roles in ensuring the success of this visionary endeavour.
Ts. Dr. Salmia Beddu is a Senior Lecturer at the College of Engineering, Universiti Tenaga Nasional (UNITEN).