Cradle to Cradle: Class question for comment

In Cradle to Cradle the introduction is titled “This Book Is Not a Tree.” The authors refer the material it that the book is comprised of as a “technical nutrient.” There is an implied assumption that this is a good thing. Is it? …why do you think so… or why not?

California Academy of Sciences Loses LEED Race. Wait, What’s LEED?

As reported by Curbed, the California Academy of Sciences recently lost the race to build the first LEED Platinum certified museum. They had to concede defeat to the Water + Life Museums in Hemet, California, which apparently came about when, after the construction of a local reservoir in the 1990’s, several significant fossil finds were unearthed, which ended up needin a home. Naturally, the response is “let’s build a green museum!” rather than, “where are we going to get the money for this?”

The LEED (Leadership in Energy and Environmental Design) Green Building System was introduced in 1998 to provide a standard by which the “greenness” of buildings can be measured, and is comprised of several itemized categories. Each category has a number of attributes that, if met, contribute to the LEED point total, which then in turn determines your certification level: Certified, Silver, Gold, or Platinum. Whereas you’d only need a minimum of 38% of the available points to earn a Certified rating, Platinum requires 76% or more. Everything from adding public transportation access to switching to less-offgassing glues counts, which means that Platinum is a serious commitment to making a building more “green”. Only about 75 buildings or building projects so far have been rated (or are gunning for) LEED Platinum, versus almost 500 that have the Certified rating (LEED maintains a list of projects). The relatively large ratio of Platinum to Certified would suggest that the LEED system is indeed working, incentivizing new projects to be “greener”.

The U.S. Green Building Council (the non-profit behind the LEED standards) has also branched out into creating separate rating systems for buildings like schools, retail outlets, and even residences. It is not, however, without its weaknesses. Often cited is the fact that once a building is LEED rated, its certification need not be renewed, leaving the social engineering door wide open for abuse (leaving computers on, running the A/C cool, etc). Perhaps the next LEED standard, 3.0 (YouTube), will attempt to address these issues, along with an expected points expansion for reduction of greenhouse gases.

Meanwhile, the California Academy of Sciences’ PR department has shifted their campaign focus just a tad:

When the Academy opens its doors in 2008, the design team anticipates the museum will earn international recognition as the world’s largest LEED Platinum-certified public space.

Bamboo Bikes

In anticipation of taking the bike building class this quarter, I went up to Portland in February for the North American Handbuilt Bicycle Show. http://www.handmadebicycleshow.com/2008/. I split my time between checking out the bikes on the show floor and sitting in on some custom bike making seminars. The seminar that particularly caught my attention was taught by Craig Calfee about his Bamboo Bikes.

Calfee has been a leader in carbon composite bikes for decades. Recently he has been producing some high end frames made with bamboo tubes. The joints were originally wrapped with carbon fiber, now he uses hemp fibers. Either way the joints are cured with an epoxy resin. Bamboo bikes are not the stiffest or lightest available, but they have an aesthetic appeal. He also mentions the low carbon footprint of the bike on his webpage.

To my surprise, the seminar was not focused the construction of bamboo bikes. Instead, Craig outlined the bamboo bicycle fabrication business he is trying to start in Ghana. As a raw material bamboo is readily available in Ghana, and the population could benefit hugely from improved mobility. Craig has visited Ghana twice to teach framebuilding workshops to some local entrepreneurs. The bike design he uses in Africa is much more utilitarian than the bamboo race bikes he builds in America. It can carry roughly 200 pounds of gear over rough terrain. His goal is to spawn a business that can sustain itself employing local Ghanaians building frames from inexpensive, local, renewable resources. His hope is that the frame builders will be able to extend credit to local farmers and business people. This way the whole community can work to lift itself out of poverty. Ultimately, the business will be able to run without foreign aid.

All of the component in the frame of the bikes except for the resin, head tube, and bottom bracket shell are made from renewable materials. Instead of hemp, the frames are wrapped with a natural fiber imported from Northern Africa. It has been widely used up there for home insulation. While I have not done a LCA, I imagine the environmental impact of farming bamboo is much lower than that of mining and producing aluminum or steel tubes. Also, the bikes are easy to repair. When a bamboo tube breaks, it can be cut out and another one wrapped and cured it. If an aluminum tube breaks, the frame is headed to the scrap heap because re-welding aluminum does not produce reliable results.

I was blown away by his presentation. I had expected to hear an eccentric designer wax poetic about the virtues of an unusual material. The nobility of his goal to help people help themselves by empowering them to create bikes from renewable materials inspired me. You can check out his diary of the experience on his webpage:

http://www.calfeedesign.com/Ghana2008.htm

Awesome solar energy technology

I read a really interesting article in the New York Times today about new methods that are being developed to store solar energy so that it can be used when the sun is not shining (i.e. at nighttime or on cloudy days).

With photovoltaic plants, which are currently being used around the world, the amount of energy that can be captured from the sun is directly related to the amount of captured sunlight. For example, when the sun is directly shining on a plant that covers about 300 acres, 50 megawatts are generated. However, when a large cloud comes over, those 50 megawatts are lost in about 100 seconds.

New technologies are focused on storing heat from the sun, like water behind a dam, so that it can be used in any amount when necessary. A company called SolarReserve is currently generating a lot of buzz, and has gathered significant corporate backing. The company has built a “power tower,” which is like a water tank on stilts that is surrounded by mirrors that tilt on two axes, one to follow the sun in the course of the day and the other throughout the year. In the tower and in a tank below are thousands of gallons of molten salt that can be heated to high temperatures without reaching high pressure. This molten salt is pumped into a large storage tank, and can be piped on demand into a steam generator that powers a turbine to generate electricity. This “power tower” can supply 540 MW of heat, which can produce 250 MW of electricity, an amount that is enough to run a fair-size city.

Here is a picture of the “power tower” located in Seville, Spain:

After reading this article, I wanted to know more about worldwide solar energy demand and usage, so I did a little research. Here are some cool facts I found:
~ Worldwide photovoltaic installations increased by 2826 MW in 2007, up from 1744 MW installed during the previous year. In 1985, demand was 21 MW.
~ Cumulative solar energy production accounts for less than 0.01% of total Global Primary Energy demand.
~ The earth receives more energy from the sun in just one hour than the world uses in a whole year.
~ Two billion people in the world have no access to electricity. For most of them, solar photovoltaics would be their cheapest electricity source, but they cannot afford it.

Fiberglass to Fibergrass

I really think composites are a cool material to work with. I’ve used it a lot to build the solar car (another post for another day) and it’s great because it’s lightweight and strong. The transportation industry is moving more and more towards using composites for more a lightweight means of getting around (the 787 is over 50% carbon fiber). The problem is, carbon fiber is not particularly eco-friendly. Manufacturing it is an intensive process that involves getting a polymer (acrylonitrile) to over 2000 degrees C. Even at end of life, CF is difficult to recycle. It is commonly downcycled, ground up and used in plastic as reinforcement. At that point, the reinforced plastic is no longer recyclable.

With hopes of changing the surfing industry, a team from the Eden project has used hemp, the wonder plant, to make an all natural fiber for composites. Combining that with a balsa wood core and a resin derived from an oil producing plant, they made an all natural surfboard. California had recently passed more stringent environment regulations, causing some CA based board companies to close up shop. The team hopes that their board can help these companies “go green” and reopen.

The material properties of hemp fiber isn’t good enough to replace carbon in high performance industries, but it shows that you can still get lightweight performance while still being environmentally conscious.