Showing posts with label electricity. Show all posts
Showing posts with label electricity. Show all posts

Saturday, June 4, 2011

The Future of Lighting

It's easy to take electric light for granted. It's ubiquitous for all but the most marginalized. It's also relatively cheap. It's only on the rare occasion that you find yourself without power that you are reminded of what a big difference it makes. Indeed, light is a factor of production, important enough to warrant switching clocks twice a year as so many places still do. Electric lighting accelerated industrialization, gets kids through school and even makes neighborhoods safer.

On the horizon for this technology are the same trends that are dominating elsewhere in the push for sustainability: smaller, safer, more efficient, longer-lasting. As that process has progressed we have seen compact fluorescent bulbs make their move from offices to homes, and I predict that we will soon see wider implementation of LED lighting.

LED lights are already commonplace in many household electronics. They're bright, sharp and colorful, look like lasers and thus speak visions of a high-tech future. I personally think it would be pretty cool to reside in an environment cast aglow by these lights' particular spectrum, but there are more material reasons to prefer them, not least because they can approach the same quality of light more conventional alternatives offer.

To start off with they use less energy to produce a given amount of light. For instance, straight from Wikipedia I've learned that a 7 watt LED bulb can produce as much light as a 60 watt incandescent bulb or a 15 watt fluorescent bulb. Beyond that LEDs live longer than incandescents by 30 times or more, with the latest fluorescents capable of shining for a comparable length of time. That's at least 30,000 hours, or 25-30 years.

Something lasting that long demands a comparable investment and for that reason LED bulbs are still pretty pricey. As is the case with all good things, that price is coming down. Whether or not it makes sense for you to put that money into a bulb you might forget or smash when you move depends on how inconvenient it is for you to front those funds and how inconvenient it is for society should you opt for something else - I wonder what the social costs of night vision goggles are. As long as you're not living hand-to-mouth though, the higher price should be more than offset by savings on energy and maintenance.



Speaking of a cool sci-fi future I now come to our second prospect on the horizon of lighting technology: bioluminescence. Bioluminescence, that alluring biochemical reaction that led more kids to aspire to become marine biologists than research funding could support, is not just for jellyfish. Genetic engineering long ago gave us glow-in-the-dark tobacco and monkeys as well. The next step is bioluminescent trees to replace street lights.

This idea has already been pretty well-documented. Here I will make the hardly profound observation that lighting in this form wouldn't require electricity. What interests me more though is the idea that overtaxed avenues of energy transformation can be relieved by redistributing that weight to other paths, and that one of those paths runs through life.

Is biology the answer to an electricity shortage? It seems to make increasing economic sense to produce what we need - light, industrial chemicals - not by the conventional means of combustion, electricity or mechanics, but by the pathways that exist within plants, animals and other organisms. That's an alarming thought when one considers the ways in which we have already exploited life. It could lead to some pretty freaky developments. We could also spare other species and engineer ourselves to see in the dark, which, again, would be pretty cool.

As long as such technology is used for the purposes of making human existence - and thus the planet - more sustainable, I find little cause for concern in engineering trees and other organisms. In the development of alternatives for lighting we have captured a glimpse of the greater integration with biology that will take place in many other areas.

Tuesday, March 1, 2011

Emerging Green Technologies: Alternative energy, biofuel and bioplastic

The "Cleaner" episode of PBS's Making Stuff investigates essentially all the same issues this blog does. I would feel redundant if that concern weren't outweighed by a much greater sense of direction and inspiration furnished by the initiatives showcased here.


Watch the full episode. See more NOVA.

The central theme of this episode is that using petroleum-derived electricity and materials to meet energy demands and structural needs too often results in persistent and undesirable side effects. The good news is that sustainable alternatives are quickly emerging to replace them. Here are the highlights:

Alternative Energy Technologies

1. Batteries & Electric Cars
Gasoline is one of the most conspicuous misuses of fossil fuels. We can phase it out of the market by designing better electric cars, but that inextricably necessitates the invention of more efficient batteries.

Conventional car batteries produce current in a lead-acid mix, but by using arrays of lithium-based batteries and an internal nanostructure that facilitates the flow of electrons, electrical output can be increased. This is an opportunity currently being explored by A123 Systems.

Unfortunately, battery-powered electric cars still require an external energy source to charge batteries. This wouldn't be a problem if our energy came from renewable sources like the sun or wind, but since we still predominately rely on fossil fuels to produce our electricity, making the switch to electric cars by itself would do little to address pollution and climate change.

2. Hydrogen fuel & fuel cells
General Motors is currently testing its model of hydrogen vehicle. The advantage of this technology is that the only byproduct resulting from its operation is water. As is the case with electric vehicles, hydrogen-powered ones require an external energy source. In this instance, it is required for the production of hydrogen gas.

An additional barrier to the widespread adoption of hydrogen vehicles is that hydrogen fuel must be stored under high pressure in order to fit within a car and even then cannot propel it as far as an equivalent volume of gasoline. The show zoomed in on this design challenge for an interesting segment on the natural materials readily available to overcome it.

The answer is feathers. University of Delaware professor Richard Wool has come up with the solution of heating them to form intricate carbon structures that expedite the concentration of hydrogen. He has in mind taking advantage of the copious amounts of chicken feathers tossed aside as a waste product in meat production. They come extremely cheap and are probably the cheapest possible solution to engineering obstacles in making hydrogen cars more competitive. Using feathers in this way serves the dual purpose of utilizing an otherwise expendable renewable resource and providing an alternative to functionally similar but cripplingly expensive man-made carbon nanotubes.

3. Biofuel
Instead of satisfying our fuel needs with substances derived from oil, we could use clean-burning alternatives made directly from plant matter. Ethanol is probably the most visible fuel in this arena and is commonly derived from corn and sugar. What's more, large scale production of biofuels could also be based on non-food crops, such as switchgrass, which may differ in nutritional requirements and restrict crowding out of food supplies.

Whatever the input, the production process of biofuels is benefiting from advances in biotechnology. Professor Jay Keasling of UC Berkley is behind the creation of genetically-modified bacteria that can produce clean-burning fuels that need no refining. This prospect stands to become a practical reality with more research in areas of genetic engineering and synthetic life. It would also translate into relatively few transition costs as fuel produced in this way would already be compatible with our combustion engine economy and associated infrastructure.



Alternative Material Technologies

Bioplastics
Ford is in the process of replacing 10% of the petroleum-derived plastics used in its automobiles with bioplastics. These include foam made from soy for seat cushioning and wheat-based details.

The host of the show, possibly in jest, says that it takes 400 steps to go from wheat to bioplastic, but I still wonder whether the technology to do so wasn't available before the advent of conventional plastics.

Mushroom mycelium is another key substance in the production of bioplastics. More information on it is available from this TED lecture by Eben Bayer, a designer who helped develop and commercialize the technology.




It's reported in the show that "only a third [of our plastics] can be replaced with bioplastics" and that the remaining two-thirds consists largely of cheap, disposable thermoplastics. The featured technologies for dealing with them involve incinerating them in closed systems by which the release of toxic and greenhouse gases is reduced to negligible levels and carbon nanotubes or electricity can be produced.

Although it offers a way of processing extant plastic pollution and added benefits, the problem with this type of waste treatment is that it requires that no plastic escape waste management channels. Moreover, it uses a lot of energy itself and while it doesn't produce emissions it does leave solid remains, the contents of which I can only imagine but guess likely contain heavy metals and other disruptors. I am hesitant to offer these approaches as solutions to our waste issues as they could easily be used to justify rampant waste, impulse buying and other detrimental behaviors symptomatic of a disposable lifestyle.


The remainder of the program discusses how giant batteries based on aluminum smelters can make the electrical grid more efficient and Bloom Energy, which offers localized electricity production at a fraction of the price and footprint, but I am most intrigued by artificial photosynthesis, which ties back into alternative energy.

Professor Nate Lewis of Caltech is spearheading practical applications of artificial photosynthesis. The technology is similar to that used in solar cells, but tweaked to allow for greater robustness and lower costs. When submerged in water Lewis' cells split it up into its constituent components of hydrogen and oxygen, allowing for the storage of energy in hydrogen fuel which could be used to power the electric cars mentioned earlier or anything else. Lewis is in the process of scaling his innovation for commercial use, but it can't happen quickly enough.


Seeing these exciting projects gives me hope and makes me wish that I could take a greater part in their development. Part of me wishes I had studied materials science. That might come later down the line.