The Potential of Piezoelectricity

I was out for a run earlier today when I recalled an article I had read sometime last year about a group of students who had worked out a way to utilize the power of footsteps on the sidewalk and cars on the road.  The source of the power comes from the simple pressures and vibrations of passing pedestrians and vehicles on a system designed to convert that kinetic energy into stored electric energy through a process known as the piezoelectric effect.  A quick look over at Wiki will tell you that this effect was first studied in the late 19th century and has been used for a variety of applications ever since.  Anyway, I got to thinking how useful this type of system would be in a large urban center at, say, a major race.  The runners' own feet could help power the very event they are participating in!  Well, turns out, as with many great ideas we have, someone already thought of it and implemented it.

Laurence Kemball-Cook founded Pavegen Systems Ltd. back in 2009 after developing his recycled rubber "Pavegen" pavement slabs that harness the piezoelectric effect.  It has taken a few years for his concept to gain steam, but just last month at the 2013 Paris marathon, thousands of runners cruised across 25 meters of these tiles, each step generating about 8 watts of kinetic energy to be captured and stored for later use.  This fascinating technology is not without it's pitfalls.  A 2010 Pop Science article referencing the Sustainable Dance Club in Rotterdam quotes a study claiming that the concept just isn't energy efficient enough.  Pavegen seems to have overcome this hurdle, though Kemball-Cook won't reveal exactly how his invention works.  A recent Design News article notes that the device even manages to harness enough power to divert some energy for data capturing, allowing city administrators to better map pedestrian traffic, leading to "smarter" cities.  The slabs even light up with each step, creating an interactive user experience.  A 2011 CNN article discusses the cost issue, which may be the reason this product hasn't quite taken off yet, and Kemball-Cook has also been tight-lipped about the cost of his device.  However, he does claim to have cut the cost in half in the last year, which is promising.  You can check out his 2012 Ted Talk here.

But even with a cheaper device or components, the design appears to require removing the current surface and building the Pavegen slabs right into the ground.  Besides the actual device, this installation and inevitable on-site maintenance will continue to pose a prohibitive cost.  A potential design to bypass this problem would be to build the slabs onto large strips that could be rolled out for big events such as races or festivals.  This would save time and money on installation.  Additionally, maintenance and repairs could be done at the manufacturer's location instead of sending a team to the site any time the device breaks down.  Of course, this would only work for temporary settings, but it could help offset the energy use of large events held in urban areas.  But as I mentioned before, I'm sure some clever engineer at Pavegen (if not Kemball-Cook himself) has already toyed with this concept, so hopefully we  something like it is already in the works.

As for that original article that popped into my head during my run, it may have been this one from Yanko Designs.  It's got some cool mock-ups (purportedly from G.E.) of a fully outfitted piezoelectrically powered intersection.  Considering the high walkability of NYC and the propensity of inhabitants to frequently don their running shoes en masse, I hope Pavegen (or some other enterprising organization) can work out the kinks and costs of this intriguing technology and we begin to see it soon throughout our Fair City.

Group of students start harnessing the underground!

Today I had an impulse to search this old concept I'd thought about (and written about) and lo and behold! Just recently a group of students in New Delhi have begun prototyping mini turbines to capture the subway wind at the entrances of stations. "Theoretical work" has shown promising numbers. Check it out on Green Optimistic's site.

http://www.greenoptimistic.com/2013/02/28/micro-wind-turbine-subway-india/#.UTAskTK9Kc0

Additionally, I've discovered that having a rigid format  for this blog (i.e. one big topic per month) greatly dissuades me from actually doing any blogging.  Therefore, going forward, this space will mostly be where I post links to articles relevant to Sustainable Urbanity, maybe with some brief commentary.  Occasionally, I might throw in a long piece if something particularly catches my fancy, so stay tuned!

Crowdfunding Sustainability

Another central focus of this blawg will be the role of crowdfunding in creating a more sustainable city.  If you are unfamiliar with the concept of crowdfunding, you can skim the first part of a paper I wrote at the end of law school (Spring 2012) here, in Google Doc form.  The second half relates to the Bloomberg administration's PlaNYC 2030 and how some of its goals could be achieved through the use of crowdfunding.

The concept of crowdfunding is nothing new.  Charities and governments essentially do the same thing; pooling large amounts of money from multiple individuals to complete certain projects or achieve certain objectives.  The major difference with crowdfunding is that the project is in the hands of a talented and motivated person or persons willing to share a concept with the world and ask anyone and everyone for some cash to bring it to life.

The model of crowdfunding addresses the disconnect that can be observed with charity donations and (most certainly) taxes.  Sure, we benefit from the pooling of our collective wealth, from the roads and subways our governments build, to the food drives and low-cost counseling charities provide, but the ends are usually so far from the initial monetary means, we lose interest.  Crowdfunding allows the individual to directly fund the projects he or she approves of, thereby gaining a personal sense of responsibility as well as a shared sense of ownership that creates positive peer pressure on the initial planner to complete said project.

The most high profile crowdfunding site these days is Kickstarter (their blog can be found to the right), though there are many out there which will surely be referenced in this blawg from time to time.  Where Kickstarter broke the mold back in 2009 was by introducing the idea of "rewards".  With their reward system, donors receive a unique token of appreciation from the artist or designer whose project is being funded, commensurate with the amount of the donation made.  Initially, Kickstarter focused mostly on artistic and musical projects, but has expanded to include almost any type of project imaginable.  They recently released their Best of Kickstarter 2012, if you're into reading some stats.  This past year was an impressive one for the young site and with the passage of the JOBS Act last spring (a summary of its passage and contents can be found in the middle part of my aforementioned paper), I believe 2013 will be a blowout year for crowdfunding.

My interest in this rapidly expanding phenomenon is its potential for furthering, you guessed, sustainable urbanity.  This type of crowdfunding is sometimes referred to as "civic crowdfunding" (see Citizinvestor and Neighbor.ly).  Civic crowdfunding uses a platform similar to Kickstarter to fund projects that would usually be left up to government agencies, possibly in partnership with some massive corporate entity looking to polish its image, such as a pocket park or public art project.  Now, the individuals who will have the most to gain or lose from such a project (i.e. those in that live in the surrounding areas) can have a say and buck in what goes on their neighborhoods.  The potential of this form of funding for sustainable urban projects is very exciting and will be discussed on this site very often (seriously, you can read more about it in my paper, though it does get a bit repetitive near the end).

With rising interest in urban renewable energy and sustainable living, and the growing popularity of crowdfunding, we NYCers will become more willing and (maybe more importantly) more able to affect positive environmental change in this beloved city of ours.

"Water" at the top of community sustainability issues last year

Sustainable Cities Collective director Kaid Benfield notes that water was THE community sustainability issue to reach "critical mass" this year, with several major projects and in-depth reports coming from various organizations in some of our biggest cities, including Chicago, D.C., and NYC.

You can read the full post here, which outlines all of Benfield's picks for "Best of 2012 in Green Community Solutions".

Addendum: Benfield has also already posted in this new year about his 5 Most Important Sustainability Stories of 2013.  In the wake of Superstorm Sandy and the intractability in Congress, Benfield remains somewhat optimistic that the trends towards urban sustainability and against suburban sprawl will continue.  Sustainable Urbanity will be keeping an eye on these stories as well, so stay tuned!

New Year's Resolution

In the new year, this blawg will focus on a different source of renewable energy and sustainability for urban areas each month.  January will be "Water Month".  Posts will cover hydroelectric power generally, as well as tidal power, wave power, and the more obscure "osmotic power" (deriving energy from the salinity gradient of salt water).  I hope to find more pros than cons in some of these novel ideas, as well as discuss the potential legal framework regarding their implementation in the briny deep surrounding our Fair City.

Happy Holidays, everyone, and Stay Green!

Definitions

old posts from law school research

Some windy ideas for NYC

Recently, the Bloomberg administration reaffirmed its commitment to increasing the wind power of NYC.  Mireya Navarro of the NY Times recently wrote about the DEP’s plans to explore ideas for installation of turbines atop the Fresh Kills landfill.  The article focuses mainly on the potential of off- or near-shore wind exploration, but the environmental effects of this kind of development are still largely undetermined.  Where I think the future of urban wind power will come from is right above our heads.

The Zone Green Text Amendment would amend several portions of the original 1961 zoning amendment, including allowing for the development of  wind turbines “up to 55’ tall beyond the zoning height limit in those situations where potential for wind energy generation is more likely” (according to their FAQ page).  As with any zoning amendment, there is a massive amount of law to consider.  As Katharine Jose of Capital New York points out, the original 1961 amendment has swelled to some 3,500 pages.  One must also consider the myriad of agencies across all different levels of jurisdiction when implementing this kind of legislative change. As it’s written, this amendment would not force any new product or behavior on people or businesses, but would merely ease the process of greening a structure.  This fits in nicely with our independent attitudes, but it means the change will have to be spurred on by some type of marketing or publicity campaign (maybe our old friend Birdie can help us out with this).

Related to this is the Not-In-My-Backyard (or NIMBY) attitude towards urban turbines (or “urbines” as World Architecture News has dubbed them), which I never understood considering some of the beautiful concept designs for turbines that are out there.  I’m extremely fascinated by the potential of vertical turbines, which function regardless of the way the wind is blowing.  Furthermore, their vertical nature causes less of the rotational frequency issues experienced with the more familiar horizontal axis turbines.  A recent paper by M. Ragheb discusses in detail several potential architectural designs that could improve rooftop efficiency, as well as the research still needed to be done and other experimental turbines that have already been placed atop buildings across the world.  Once the wind potential for these types of designs has been further studied and refined, it could catch on the architectural community, especially if the end result is more money in people’s pockets.

As I said before, the future of urban wind power will come from right above our heads; it may very well come from below our feet too.  Have you ever been waiting on the subway platform, possibly at one of those stops that comes after a long tunnel, like Clark St in Brooklyn Heights, and felt the rush of air being pushed by the oncoming train?  Maybe you’ve thought, as I have, “wouldn’t it be great if we could harness all this wind potential?”

As Leora Broydo Vestel of the Times reported in 2009, some cities are already considering placing wind turbines alongside highways to recapture wind generated by passing motorists.  This is an awesomely green idea, taking waste energy produced by gas-guzzling cars and turning it into emissions-free electricity.  Unfortunately, this angle doesn’t benefit NYC too much, since average vehicle speeds, even along the city’s major highways (FDR, BQE) are notoriously slow.  However, plans have been developed in South Korea and China to harvest the windy power of their trains and subways.  China’s plan relies on an ingenious invention called the “T-box” which is basically a mini-vertical turbine, placed on its side, and installed between the rails, capturing wind pushed down and under the train.  Of course, these plans still require lots of R&D and the costs of installation and maintenance are still unknown.

NYC and the Mayor’s Office would do well to invest in this kind of research and see what parts of our subway and commuter rail lines could be used to best harness this waste energy.  I imagine vertical turbines being placed next to (or in lieu of) the load-bearing pylons along our subway platforms, churning away day and night as each train pulls into and out of the station.  These turbines could be plugged directly into the third rail, powering the very subways that are powering them!  Wouldn’t that be something?