Horizontal/Subsurface Infrastructure & Transportation

Hello.  Our group at Univ. of Texas at San Antonio has come up with a prototype to harvest mechanical energy from roadways and convert it into electric power using Piezoelectric transducers. I think this will be a great approach for State DOT to make use of current assets for revenue making.  Using this technology under pavement can provide power for sensors and low-watt LED for lighting. Also, with minimum use of right of way it could be an alternative technology to solar panels along roadway as commonly used in Europe.  I am curious if this would be of an interest to State DOT or FHWA especially as we enter the V2V and V2I arena?  Any thoughts?

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Samer Dessouky Ph.D., P.E., F.ASCE
Associate Professor
University of Texas at San Antonio
San Antonio TX
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This is an interesting and innovative concept.  The issues with just about anything in public rights-of-way are capital cost, maintenance cost, reliability, and potential impact to other structures and facilities within the r.o.w. This technology would integrate energy generation, something DOT's are not in the business of doing, with transportation.  Not only that, it would insert a new and relatively unproven element into the pavement subgrade and this would have some consequence in the design and performance of the pavement.  It may also influence constructability and duration of construction, as well as potential connection issues.  Issues like, how would the system impact pavement repair and maintenance, power purchase agreements, collection and transmission requirements, power conditioning, and substation infrastructure, etc. would have to be worked out to make this a technology that can be incorporated in roadway construction.  There would have to be bases for design, project viability assessment, etc.  I would think a full scale demonstration project (something like Virginia's Smart Road) would need to be completed to show how this technology could be constructed and function before it could be accepted for broader use.  Despite the potential for such technology, I would think a considerable amount of work would have to be done to gain DOT acceptance.

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Michael Byle P.E., D.GE, F.ASCE
Tetra Tech Inc.,
Langhorne PA
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What could this do for P3? Income to help fund a road project? Reduce the Concession Time? Fall to the State/Local DOT to continue, maintain and update when Returned in a Sate of Good Repair?

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Gerald Cichy P.E., M.ASCE, AICP
CONSULTANT
Rockville MD
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Original Message:
Sent: 04-06-2017 09:53
From: Michael Byle
Subject: Piezoelectric transducers

This is an interesting and innovative concept.  The issues with just about anything in public rights-of-way are capital cost, maintenance cost, reliability, and potential impact to other structures and facilities within the r.o.w. This technology would integrate energy generation, something DOT's are not in the business of doing, with transportation.  Not only that, it would insert a new and relatively unproven element into the pavement subgrade and this would have some consequence in the design and performance of the pavement.  It may also influence constructability and duration of construction, as well as potential connection issues.  Issues like, how would the system impact pavement repair and maintenance, power purchase agreements, collection and transmission requirements, power conditioning, and substation infrastructure, etc. would have to be worked out to make this a technology that can be incorporated in roadway construction.  There would have to be bases for design, project viability assessment, etc.  I would think a full scale demonstration project (something like Virginia's Smart Road) would need to be completed to show how this technology could be constructed and function before it could be accepted for broader use.  Despite the potential for such technology, I would think a considerable amount of work would have to be done to gain DOT acceptance.

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Michael Byle P.E., D.GE, F.ASCE
Tetra Tech Inc.,
Langhorne PA
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Our study demonstrated the proof of concept on the viability of this technology in producing power under traffic. The experimental work also demonstrated the long life span of the piezoelectric transducers (with sealed enclosure against damage/water) of expected 20 years. The applied traffic stresses are much lower than the strength of these materials. In Our experiment, we attempted to install them flush with pavement surface to maximize the power output. Other alternative is to install them during overlay operation under 2 inch of pavement to reduce installation/delay cost. 

As most of you remarked, a full investigation on long-term pavement performance and a cost-benefit analysis are yet to be conducted. we are in the process to finding answers to those questions. Our completed study only covered the numerical and experimental analysis and a brief field demonstration under control passenger vehicle.

This effort is one of the approaches we attempted towards enhancing sustainability and transportation economics through multi-use of right-of-way.

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Samer Dessouky Ph.D., P.E., F.ASCE
Associate Professor
University of Texas at San Antonio
San Antonio TX
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Original Message:
Sent: 04-06-2017 09:53
From: Michael Byle
Subject: Piezoelectric transducers

This is an interesting and innovative concept.  The issues with just about anything in public rights-of-way are capital cost, maintenance cost, reliability, and potential impact to other structures and facilities within the r.o.w. This technology would integrate energy generation, something DOT's are not in the business of doing, with transportation.  Not only that, it would insert a new and relatively unproven element into the pavement subgrade and this would have some consequence in the design and performance of the pavement.  It may also influence constructability and duration of construction, as well as potential connection issues.  Issues like, how would the system impact pavement repair and maintenance, power purchase agreements, collection and transmission requirements, power conditioning, and substation infrastructure, etc. would have to be worked out to make this a technology that can be incorporated in roadway construction.  There would have to be bases for design, project viability assessment, etc.  I would think a full scale demonstration project (something like Virginia's Smart Road) would need to be completed to show how this technology could be constructed and function before it could be accepted for broader use.  Despite the potential for such technology, I would think a considerable amount of work would have to be done to gain DOT acceptance.

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Michael Byle P.E., D.GE, F.ASCE
Tetra Tech Inc.,
Langhorne PA
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I have had more than a curiosity about piezo applications.  Your concept prototype has application potential.  Playing devil's advocate, I would want to assess via a value analysis study.  Specifically speaking, how does the sum of material(s) and installation costs relate to payback, and, what length of time must evolve before the break even point of return to investment is reached?  My focus being that the realistic life span of pavements on interstates is 5-7 years for A/C and maybe 20 years for PCC.

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William Belcher EIT, A.M.ASCE
Advisor/Consultant
Springfield OR
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In California, there have been legislative attempts to mandate the use of piezoelectric transducers in state highways.  They have usually failed due to what the other commentators pointed out - lack of details as to benefits versus the costs in maintaining and future repair/replacement.  There is interest but what is needed are details (e.g. impact on maintenance efforts; costs to install, replace; power generated; effect of speed on the power generated; etc..  Once the viability of the concept is demonstrated, then the politics and policy would need to be addressed by each state.

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Robert Effinger P.E., M.ASCE
Project Delivery Managment Liaison
Carmichael CA
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Has this concept been tested in northeast-like weather (snow, salt, hot..)?

K. Siva

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Umakanthan Sivapalarasah P.E., M.ASCE
Fairfax County Department of Public Works
Fairfax VA
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Original Message:
Sent: 04-10-2017 10:16
From: Robert Effinger
Subject: Piezoelectric transducers

In California, there have been legislative attempts to mandate the use of piezoelectric transducers in state highways.  They have usually failed due to what the other commentators pointed out - lack of details as to benefits versus the costs in maintaining and future repair/replacement.  There is interest but what is needed are details (e.g. impact on maintenance efforts; costs to install, replace; power generated; effect of speed on the power generated; etc..  Once the viability of the concept is demonstrated, then the politics and policy would need to be addressed by each state.

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Robert Effinger P.E., M.ASCE
Project Delivery Managment Liaison
Carmichael CA
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Cost effectiveness is the question.  There is technology out there to do it, but is the existing technology anywhere near cost effective?  The concept does raise an interesting angle though:  The heavier the vehicle the more damage is done to the roadway while the more energy can be  produced.  However, there is no such thing as a free lunch.  The energy produced has to come from somewhere.  In this case it would come from the fact the tires are constantly climbing out of the depressions from the deflections creating the energy.  Could be sort of a tax as you go...

I would disagree with the longevity of both AC and PCC pavements though.  AC modified with elastic polymers can last much longer than 7 or 8 years.  In fact, higher concentrations of SBS are workable with warm mix and other additives, and recent research has shown the asphalt, and not the SBS, is what breaks down.  With proper periodic rejuvenation of the asphalt material the actual life of the AC increases dramatically.  I was also recently involved with reconstruction of PCC pavement on I-10 that was 50 years old.  The passing lanes were still in acceptable condition, but due to interface questions between the lanes (AC new) and the fact they were already reconstructing the driving lanes the passing lanes were replaced as well.

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Stephen Hemphill P.E., M.ASCE
Semi-Retired
Rio Rancho NM
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Original Message:
Sent: 04-17-2017 09:19
From: Umakanthan Sivapalarasah
Subject: Piezoelectric transducers

Has this concept been tested in northeast-like weather (snow, salt, hot..)?

K. Siva

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Umakanthan Sivapalarasah P.E., M.ASCE
Fairfax County Department of Public Works
Fairfax VA
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