Synthesis of Using Emerging Energy Harvesting Technologies in Transportation Infrastructure
Transportation infrastructure is traditionally
considered a means of fulfilling the mobility needs through connecting
communities via commerce and moving people. Financial resources to build and
maintain these infrastructures come, for the most part, from fuel taxes (20
cents/gal). However, with increasing numbers of lane-miles added to support the
expansion of the population away from cities, and as vehicles become more fuel
efficient, funding for maintenance is becoming scarce and our infrastructure
will, inevitably, continue to deteriorate. Millions of lane miles subject to
solar heat and vibrations, combined with repeated strains under normal working
conditions, make these infrastructures great sources for energy harvesting. The
current wasted energy can be transformed using efficient systems into usable
electric power. Using these infrastructures as a means of harvesting energy is
a relatively novel idea that has not been fully implemented yet. Massive
amounts of mechanical strain energy is wasted when millions of vehicles are
moving on roadways, railways, and bridges. The emerging harvesting technologies
can harvest the wasted energy, feed the harvesting energy to the power grid, or
save the generated electricity in batteries to charge electric vehicles and
power roadside lights, traffic signs, and monitoring sensors. The following list highlights the economic benefits
and environmental impact of energy harvesting technologies.
Energy harvesting technologies are:
completely green, having no environmental impact, as opposed to energy
generated from burning fossil fuels,
take up no public space as the energy
harvesting technologies use existing right of way,
can be implemented in rural infrastructure
providing sources of power to remote areas,
use available energy resources from traffic
loads, heat, and vibration (not requiring wind, sun, or geothermal sites),
enable a “smart” infrastructure by gathering
real time information on vehicle weight, speed, and traffic volume.
Energy harvesting technologies are not new, but the
feasible applications of the technologies in transportation infrastructures are
yet to be quantified. Preliminary literature review suggests that the energy
harvesting technologies are taking steps for full deployment in Europe roadways
however, limited studies have considered the application of the energy
harvesting technologies in the United States roadways to date. Currently,
California is investing in developing Piezoelectric-based technology for
potential implementation and Virginia conducted limited field-testing on their
smart road. The Piezoelectric-based technology is a great opportunity for state
DOTs to consider for an energy harvesting technology as a source of revenue to
raise the economic impact and lower the environmental impact of each DOT’s transportation
Revenues for integrating the
generated power from energy harvesting technologies can be used for infrastructure
maintenance funds and to offset the reduced revenues from gas taxes. Continuous
monitoring of infrastruture will save Department of Transportation (DOT) the associated cost of diagnostics.
Collected traffic data can be fed into a traffic management system. Incoporating the generated power for improving
street illumination will improve safety in remote areas.
There are numerous
technologies that surfaced over the last few years in an attempt to use
transportation infrastructure in harvesting energy. Some technologies are
having unique characteristics and advantages over others depending on their
applications. For instance, PZT a candidate technology for railways and steel
bridges to convert vibration into useable energy but not in asphalt roadways. Therefore,
the objective of the study is to “develop a synthesis document on the current
energy harvesting technologies and their feasible applications in
transportation infrastructure”. The proposed tasks of the study are:
- Summarize state
of knowledge on existing energy harvesting technologies with promising
applications on transportation infrastructure.
- Develop a
guideline document comparing the energy harvesting technologies on the basis of
their operation mechanism, energy output, functionality, durability, environmental
impact and cost.
recommendations on their feasibility, obstacle for implementation and potential
use in transportation infrastructure.
A guidance document will be created and become a reference for DOTs on
how to identify the optimum harvesting technology for particular application in
infrastructure to maximize environmental and economic benefits. The guidance document will also include a
process to evaluate the potential environmental impacts and economic gain when key
parameters (e.g., traffic load and volume) are identified.
This study will answer the following questions:
are the potential energy harvesting technologies for transportation infrastructure?
are the economic benefits and the environmental impacts of integrating these
are the best-practices or lessons learned from the case studies on implementing
these technology on infrastructure?
are the needs for expanding the use of these technologies to maximize their
harvesting (scavenging) is a process that captures unused ambient energy that
would otherwise be lost in the form of heat, vibration, stress, or deformation.
Roadways, bridges, and railways are exposed to energy from wheels’ movement,
loading, and solar heat. These resources can be potentially converted and
stored into usable electric power. Energy harvesting can lead to sustainable
transportation infrastructure. Examples of current technologies to harvest
Energy harvesting using solar collector: The heat in an asphalt pavement
surface is accumulated during the day due to the absorption of solar radiation.
The concept of an asphalt solar collector involves a piping system that collects
pavement heat through an appropriate fluid (Mallick et al. 2009). The piping
system can reduce temperature of pavement and surrounding ambient air
ultimately reducing the urban heat island effect (De Bondt 2003). However, the
structural integrity of the piping system under intense heat and repeated
impacts of traffic loads is a still a major concern for roadway engineers. The
solar collector technology is highly dependent upon climate conditions and may
not be universally viable.
harvesting using TEG: The
temperature of an asphalt roadway structure is typically higher at surface and
lower at deeper layers, creating a thermal gradient across the pavement (Datta
et al. 2016). The thermal gradient can activate thermoelectric generator (TEG) materials
to generate electric power. Inserting TEG materials in roadway structures can
convert the thermal gradient heat into electric voltage using the Seebeck
effect (Liang and Li 2015).
harvesting using piezoelectric transducers: Under traffic loading, pavements are exposed to
vibrations, strains, and compression forces that form mechanical strain energy. The mechanical strain energy can be captured
and converted to usable electric power using piezoelectric transducers (PZT)
(Hill et al. 2014; Ali et al. 2011). PZT have the property of generating an
electric voltage when subjected to deformation by dimensional alteration or
vibration. Xiong (2014) designed and installed nine different PZT energy
harvesters for roadway applications. The
conclusion was that the output power from PZT was very low but enough for
powering structural health sensors network.
harvesting using photovoltaic: The
principals of solar roadways is to use embedded (surface) photovoltaic
technology for harvesting solar energy. The photovoltaic technologies are
incorporated into the surface replacing the traditional asphalt pavement
materials currently used. In 2006, Solar Roadways Inc. built a parking lot
covered by solar panels (Mehta et al. 2015). The solar panels in roadway are
integrated with heating elements to maintain above freezing temperature. In the
Netherlands, the SolaRoad built a 230-feet bike lane with solar panels made of
thick glass layers to withstand heavy loads. SolaRoad expects that the power
generated from the panels to exceed 3 megawatt-hours after six months from
opening (SolaRoad 2016). In December 2016, France constructed the first kilometer-long solar road coated
with a clear silicon resin that enables them to withstand the impact of passing
traffic. Major concerns are the roads durability to resist traffic
impact and preserving surface texture for the safety of motorists. Also, the
effect of shading caused by obstructions from buildings, trees, cloudy
conditions and from passing vehicles may impact the efficiency of solar roadways.
reviewed information detailed various technologies, but the technologies did
not provide guidance on the best practices of using them in infrastructure for
maximizing economic and environmental benefits.
Task 1: Canvas
transportation agencies for energy harvesting success stories
- Obtain sample
Task 2: Canvas regulatory
agencies and assemble a state-of-the-practice vision on energy harvesting technologies and the concerns
the agencies think need to be addresses to make such implementation of
Task 3: Canvas DOTs to
obtain existing analytical data on different energy harvesting technologies
- Ex. Solar
collectors, TEGs, Photovoltaic technologies, etc.
Task 4: Synthesize
characteristics of energy harvesting
Task 5: Identify areas of
optimal use for the technologies
Task 6: Create life-cycle
costs and risk analysis for energy harvesting success stories
Task 7: Evaluate benefits
and risks of implementing energy harvesting technologies within ROW
Task 8: Identify and
evaluate existing policies concerning energy harvesting technologies on
roadways and ROW to help agencies make appropriate changes to practices,
equipment, facilities, or agency policies when using energy harvesting technologies.
Identify gaps in
existing practices and policies
information into more “readable” format
existing practices, training materials, or products into single repository
State DOTs are aware of the
rising costs pf maintenance and lower amounts of revenue being provided. The
DOTs are learning about possible ways to generate more revenue and have a more
comprehensive way of collecting statistics and data about use and
deterioration. The DOTs would champion this research since the study would
provide new information about the implementation of energy harvesting
Any DOT application that requires small amounts of energy in remote locations.
|Sponsoring Committee:||AMS20, Resource Conservation and Recovery
|Research Period:||6 - 12 months|
|RNS Developer:||Andrew Graettinger and Samer Dessouky|
|Source Info:||Mallick, R.B., Chen, B. L. and Bhowmick, C., 2009. “Harvesting energy from asphalt pavements and reducing the heat island effect”, International Journal of Sustainable Engineering, 2:3, 214-228|
De Bondt, A. (2003). Generation of Energy via Asphalt Pavement Surfaces. Asphaltica Padova.
Liang, G., and Li, P., 2015, Research on thermoelectric transducers for harvesting energy
Datta U., Dessouky S. and A.T. Papagiannakis. (2016) “Harvesting of Thermoelectric Energy from Asphalt Pavements” Transportation Research Record: Journal of the Transportation Research Board. DOI 10.3141/2628-02
Hill, D., Agarwal, A., and Tong, N. Assessment of piezoelectric materials for roadway energy harvesting. Energy Research and Development Division Final Project Report, DNV KEMA Energy & Sustainability, Oakland, CA, 2014.
Ali, S. F., Friswell, M. I., and Adhikari, S., Analysis of energy harvesters for highway bridges. Journal of Intelligent Material Systems and Structures, Vol. 22, No. 16, 2011, pp. 1929‐1938
Xiong, H., Piezoelectric energy harvesting for public roadways, Ph.D. Dissertation, Virginia Polytechnic Institute and State University, Department of Civil Engineering, VA, 2014.
SolaRoad. Publications, http://en.solaroad.nl/publications/, accessed June 24, 2016.
Mehta, A., Aggrawa, N., and Tiwari, A., Solar Roadways-The future of roadways, International Advanced Research Journal in Science, Engineering and Technology, Vol. 2, Issue 1, May 2015.
|Index Terms:||Energy harvesting, Renewable energy sources, Economic benefits, Environmental impacts, Infrastructure, Emerging technology, Piezoelectricity, Sustainable development, California, State departments of transportation, |