implications of electricity prices indicate that access is not universally affordable. for low-income households, electricity costs make up a much larger share of their budget compared to more affluent families, even though lower-income users consume less electricity on average. electricity costs account for about 5.7% of the median low-income family’s budget versus 1.9% for the average family. if an impoverished household were to adopt solar as a source of power, their funds could be allocated to more critical investments, such as education. additionally, renewable energies are particularly attractive for poor families because they have the potential to become an additional source of income if excess power generation can be sold back to the utility. the problem is these households often do not have capital at hand to finance the installation. although the government spends approximately $6.3 billion on energy costs for federally-assisted housing, these expenditures often do not include renewable energy investments.

likewise, in terms of quality, consumers do not have the capacity to dictate how their energy is produced. if i wanted to power my home without releasing billions in co2 emissions or risking the world’s next oil spill, i could install solar panels on my roof. that is, assuming i have enough income to secure a mortgage, finance the installation, and reside in a suburban setting. the reality of the matter is that most americans do not have the luxury of these prerequisites. in fact, lower income earners are more likely to be renters in multi-family buildings with deferred maintenance that prioritize other upgrades before considering renewable power.

after considering socio-economic repercussions, universal access to electricity in the united states becomes a goal our nation has yet to reach. the next question this issue raises concerns the stakeholders responsible for our energy inequality. obviously, the government plays a crucial role in implementing policy and legislation that reduce the financial hurdles placed on low-income renters. in the new era of the trump administration, attaining comprehensive energy access becomes even more of a challenge. the newly elected president has already appointed scott pruitt to head the epa, an adamant opponent of obama’s clean power plan. in the coming weeks, significant cuts are expected in the department of energy’s office of energy efficiency & renewable energy, which provided millions in funding of clean technology research and development and solar-backed programs throughout the previous eight years.

however, the government is not the only contributor to energy equity progress. utilities play an indispensable role in creating incentives for distributed power generation and cooperation among homeowners, solar companies, and technology providers. this is not a problem that offers an easy solution, but with the collaboration across private and public sectors, significant progress could be achieved for equitable energy access.

the potential for piezoelectric energy seems endless with modern advances in technology, as it can and has been implemented in a variety of different outlets. for example, it is not uncommon for nightclubs in europe to possess this technology within their very dances floors, creating energy that powers the entire establishment, from the stereo to the lighting.

here in the united states, gyms exist in which stationary exercise equipment possesses this technology in order to power the gym. furthermore, the greatest potential for piezoelectric energy seems to lie in the outlet of highway and road construction. piezoelectric crystals that are placed under these surfaces that experience the vibrations of thousands of vehicles and pedestrians a day have the potential to power entire towns and communities, perhaps even nations and the world. this technology is one of the most up-and-coming in alternative fuel exploration and will most likely be implemented into a variety of technologies in the future

i used to operate a real-time x-ray machine to examine jet-engine parts but do not have that job any longer. all i would need to do is to x-ray a solar cell (or a stack of them) hooked up to a voltmeter to see if it will work. if this does work or even is remotely feasible, all of those fuel rods wasting away could be used to power many different things and in this configuration should not need a cooling system. since there would only be one rod per “battery,” the “battery” housing could be lead, tungsten, or some other material since the radiation from the rod is not too high.

photo credit to paul stevenson.

this technology isn’t unheard of; in fact, california fitness was the first organization to bring this concept to its gyms. this kinetic energy will hopefully spread to hundreds of other fitness centers around the world, and the numbers show why. according to california fitness president steve clinefelter, spending an hour on one of the exercise machines can generate up to 18.2 kilowatts of electricity. this is equivalent to preventing the release of 4,380 liters of carbon dioxide per year.

more gyms and health clubs should know the potential gains of this technology, and just how much it can benefit the environment. why waste the workouts of so many patrons when gyms could be using that energy to save money and energy?

the process of turning heated water into energy was essentially understood by james watt all the way back in 1765. heat from the sun or from a controlled nuclear reaction boils water, which then expands, moves a turbine and generates power.

why water? it is cheap; it absorbs a lot of “latent heat” as it turns into steam; it produces a lot of power as it expands through the turbine; and it is easily condensed back to liquid water using an environmental source such as a river.

heat to electricity

beginning from the fundamental research of nicolas leonard sadi carnot in 1824, engineers have learned how to manipulate the boiling and condensing of water, using this “phase transformation” between liquid and gas to generate electricity.

adding heat to the water at the right point in the cycle and preventing heat exchange at other points during the cycle enables researchers to ultimately extract the most power from the steam. in this way, they carefully designed the cycle to maximize its efficiency, a mathematical concept that carnot defined.

“this boiling and condensing of water requires massive pressure vessels and heat exchangers to contain the water,” said researcher richard james, of the university of minnesota.

james and his team of researchers want to substitute a completely different phase transformation to replace the boiling and condensing of water. they have been investigating that possibility using a family of metal alloys (specific mixes of different elements) called “multiferroic materials.”

multiferroic materials

multiferroic materials are materials that exhibit at least two of three “ferroic” properties: ferromagnetism (like an iron magnet, spontaneously magnetized), ferroelectricity (spontaneously developing two poles), or ferroelasticity (spontaneously strained). a natural way to exhibit ferroelasticity is by a phase transformation in which one crystal structure suddenly distorts into another, a so-called martensitic phase transformation.

instead of water to steam, the james’s team’s idea is to use a martensitic phase transformation that occurs naturally in some of these multiferroic materials. using a mathematical theory for martensitic phase transformations developed with national science foundation (nsf) funding, the researchers discovered a way to systematically tune the composition of multiferroic materials to be able to turn the phase transformation on and off.

usually a metal’s ability to switch phases like this is impeded by a characteristic called “hysteresis,” which is how long it takes for the magnetism of the metal to catch up with the phase change. if it takes too long, it impedes the metal’s ability to switch phases back and forth.

evolving alloys

“the key idea is to manipulate the composition of the alloy so the two crystal structures fit together perfectly,” james said. “when this is done, the hysteresis of the phase transformation drops dramatically and it becomes highly reversible.”

even after the first low hysteresis alloys began to emerge, the strategy was all based on theory. “to be sure that the hysteresis dropped for the expected reason, it was critical that we actually see the perfect interfaces in tuned alloys,” james said.

for this purpose, james teamed with nick schryvers from the electron microscopy for materials science laboratory at the university of antwerp in belgium, a celebrated center for the study of phase transformations using electron microscopy. the resulting study, by schryvers and university of antwerp graduate student remi delville, revealed perfectly matching interfaces between the two phases.

heusler alloys

the researchers pursued the concept in a family of alloys called heusler alloys which are magnetic, even though the metals that make them up aren’t. named for the german mining engineer friedrich heusler, who first noticed that cu2mnsn (copper-manganese-tin) is magnetic even though the separate elements cu, mn and sn are nonmagnetic, this family of alloys has a striking propensity to exhibit magnetism. as james notes, heuslers are also loaded with martensitic phase transformations.

working in james’ group, postdoctoral fellow vijay srivastava applied the strategy to achieve low hysteresis, systematically changing the composition of the basic heusler alloy ni2mnsn and arriving at ni45co5mn40sn10.

“ni45co5mn40sn10 is a remarkable alloy,” said james. “the low temperature phase is nonmagnetic but the high temperature phase is a strong magnet, almost as strong as iron at the same temperature.” the researchers immediately realized that such an alloy could act like the phase-transitioning water in a power plant.

“if you surround the alloy by a small coil and heat it through the phase transformation, the suddenly changing magnetization induces a current in the coil,” said james. “in the process, the alloy absorbs some latent heat. it turns heat directly into electricity.”

revolutionizing power plants

the consequences for the technology are potentially far-reaching. in a power plant, one would not need the massive pressure vessels, piping and heat exchangers used to transport and heat water. since the transformation temperature can be adjusted over a wide range, the concept is adaptable to many sources of heat stored on earth with small temperature differences.

“one can even dream of using the temperature difference between the surface of the ocean and a few hundred meters down,” james said.

together with professor christopher leighton at the university of minnesota, the researchers are also studying the possibility of making thin film versions of their devices. those could work in computers, right on the chip, to convert waste heat into electricity to charge the battery.

james emphasizes that their demonstration is just one of many ways one can use martensitic phase transformations for energy conversion.

“besides magnetism, there are many physical properties that could be different in the two phases and could be used to generate electricity from heat,” james said. “but how to develop these concepts and which ones will work best?”

“even the criterion for ‘best’ is unclear, since one does not pay for waste heat,” james continued. “really, we have to rethink from fundamental principles the thermodynamics of energy conversion at small temperature difference.”

— lisa-joy zgorski, national science foundation, lzgorski@nsf.gov

this behind the scenes article was provided to livescience in partnership with the national science foundation.

in “the light bulb ban,” energynow! correspondent lee patrick sullivan visits the lightfair international trade show in philadelphia to find the latest offerings in energy efficient bulbs. he finds a 60-watt equivalent led bulb that will be the first in the world to sell for less than $20 and the first 100-watt equivalent led bulb to hit the market in october. he also finds out how led technology is expanding to bring us bulbs that can be dimmed and programmed with a tablet computer or smart phone and wireless sound throughout the home.

tom benton of the lighting science group, maker of the under $20 60-watt bulb, explains how led manufacturers are bringing costs down. brett sharenow of switch lighting, which makes the 100-watt equivalent, tells lee patrick that the switch bulb, as it’s called, is designed as a direct replacement for 100-watt incandescent bulbs and that consumers shouldn’t be able to tell the difference between the two – until they see their electric bills. the switch bulb lasts 15 years and uses just 15 percent of the electricity that an incandescent bulb would use, so it will probably pay for itself.

but even for those who prefer incandescent bulbs, the news isn’t all bad. martha delgado of bulbright industries, a halogen light bulb maker, explains how the government’s phaseout of inefficient light bulbs works, and why consumers will still be able to buy incandescent bulbs.

their idea is to take non-essential electricity use off the grid to de-stress the system. and so they are building a network of large power users (businesses, schools, institutions, hospitals, governments, etc.), installing smart energy-management meters and monitors, and working with them to assess how much energy they can curtail on demand during those rare demand response events. in effect they are building virtual plants and in the process preventing blackouts and brownouts in regions all across the country. more info here: http://www.nicholas.duke.edu/main/dukenvironment/sp11/brewster