Honda’s new solar hydrogen fueling station

By ADC | Published: February 5, 2010
Honda's solar hydrogen fueling station is small enough to fit in your garage.

Honda's solar hydrogen fueling station is small enough to fit in your garage.

I just saw this news story, and while I don’t have time to issue commentary on it today, I think it is a neat news item. Honda just opened a solar hydrogen fueling station in California. This design is small enough to fit in a person’s garage, which helps alleviate the problem of finding a station to supply your hydrogen car with fuel. Read the full story on the NYTimes.

One issue this brief article doesn’t address is the hydrogen production method used by the fueling station and more details about the technology. I may have to dig around the internet a little more for answers to those questions…

Bottom line: Honda has a new solar hydrogen fueling station. Neat!

[Digg] [Facebook] [Reddit] [Twitter]
Posted in Energy | Comments closed

Kudos are in order

By ADC | Published: January 27, 2010
If this guy has it his way, we'll be fueling our cars with this stuff in the near future. But is it as green as it looks?

If this guy has it his way, we'll be fueling our cars with this stuff in the near future. But is it as green as it looks?

I read an article just recently that really impressed me. Many articles about renewable energy sources tend to gloss over the downsides of a particular technology and present a very simplified view of the overall environmental merit of the ‘renewable’ energy source. Perhaps simplifying the science behind new technology is the point of science review articles, but I also feel that this approach is dangerous, particularly when we make policy based on these rosy assesments. The article I’m writing about today addresses both the shortcomings of algal biofuels production and then suggests modifications that would make algae a more environmentally friendly biofuel source.

The NYTimes Green Inc. blog recently reviewed a journal article published in Environmental Science and Technology that quantifies the costs and benefits of algae production. It turns out that algae, regarded as the most promising of all biofuel feedstocks because it doesn’t interfere with food production, may actually do more harm than good in terms of its contributions to climate change.  The problem is that algae need nutrients to grow, which are delivered by dissolving synthetic fertilizers in the algae water. Nitrogen from these fertilizers volatizes to produce nitrous oxide, a potent greenhouse gas with 310 times the global warming potential of carbon dioxide. Crops such as corn and switchgrass, though, would have lower nitrous oxide emissions because they are able to absorb nutrients from the soil and require less fertilizer application. Identifying synthetic fertilizers as the culprit in making algae production environmentally unfriendly allows researchers and the public to reconsider conventional methods of algae production. The authors of the algae journal article suggest growing algae in municipal wastewater, which contains plenty of nitrogen and phosphorus that hungry algae need to grow and would decrease the required fertilizer input (and thus nitrous oxide emissions). This article and NYTimes review comes on the heels of a government pledge to spend $80 million of stimulus funds on biofuels research. What better timing than now to publish a work crucial to the development of algae mass production? Kudos to the paper’s authors, Andres F. Clarens, Eleazer P. Resurreccion, Mark A. White and Lisa M. Colosi, and also to the NYTimes Green Inc. Blog for summarizing this work in a single page story that sets the stage for a broader discussion of the environmental merits of algal biofuels.

Bottom Line: Taking a critical look at renewable energy sources and providing constructive commentary is great for ensuring that new energy technology provides the intended environmental benefits. So please, media outlets, spare us the simplified adulation of ‘green’ energy sources.

[Digg] [Facebook] [Reddit] [Twitter]
Posted in Energy, NYTimes | Tagged , , , | Comments closed

Who Killed the Electric Car?

By AKB | Published: September 24, 2009

You know when you see a really good movie and you get all pumped up about it and can’t stop telling people about it? You say stuff like “No, seriously- you need to watch this” and “It’s really interesting.” I’m not going to do that.

I try not to recommend things too often, but this film is solid. Although a bit sensational at times, the interviews and footage documenting the “murder” provide quite a bit of evidence for you to make your own decision on who killed the electric car.

Bottom Line: I’m not at all surprised that GM is in the position it’s in today having seen this movie. Seriously though, you need to watch this; It’s really interesting.

[Digg] [Facebook] [Reddit] [Twitter]
Posted in Electricity, Energy, Human Behavior, Video | Tagged | Comments closed

Carbon Cycle

By AKB | Published: September 23, 2009

This article is about carbon and how it moves around our planet. Carbon is the fourth most abundant element in the universe and the basic building block for all life. Carbon atoms are everywhere – the stone we walk on, the CO2 our bodies produce and release into the air, the backbone of polymers, and most importantly, carbon is the foundation of all life.

The total amount of carbon on the earth is essentially constant. Imagine a log of wood inside of a large sealed metal box filled with air. Weigh the entire box and its contents. Now cut the log up until it is just a pile of sawdust. Weigh the box again – it has the same weight. Now burn the sawdust inside until all that is left is a pile of ash inside a smoke filled box. Weigh the box again. The weight is the same as before.

Mass is not created or destroyed when you cut the log up or burn it. It simply changes form. If you were to uniquely label each atom in the original log, you would still be able to find every atom after the log was cut up and burned. The atoms would be arranged differently but they would all be somewhere in the box. The image below shows how a molecule of methane reacts with oxygen to form carbon dioxide and water. Energy is also released in this process which can do work for us. Click here to learn more about hydrocarbons like crude oil and coal.

Molecular combustion of Methane

Note that the atoms remain intact as go from being methane and oxygen to being water and CO2 (www.chemistryland.com)

The box example applies to the earth too. Mass doesn’t enter or leave earth unless we’re hit by something or we send a satellite into space. So if the number of carbon atoms on the planet is constant no matter what we do, then why is there suddenly a “carbon problem?” The problem is that we are converting a lot of carbon from one form to another.

When we burn fossil fuels we don’t create carbon, we just convert it from a hydrocarbon – which was previously buried under the earth’s surface – to CO2 in the atmosphere. CO2 is a greenhouse gas which means that it prevents heat from leaving the earth. If there was too much CO2 in the atmosphere, then the planet would trap too much of the sun’s energy on the surface and life would die off because of the heat.

Fortunately, the earth also has systems to take up CO2 to avoid it building up in the atmosphere. Venus’ atmosphere is over 95% CO2 and this contributes to the lead-melting temperatures on the surface of Venus. [Venus is also closer to the sun than the earth which means it receives more of the sun's energy. But the CO2 is a very important factor: Mercury which is closer to the sun than both Venus and Earth, never has temperatures as high as Venus' because there's hardly any CO2 in Mercury's thin atmosphere. This thin atmosphere doesn't trap any heat on the surface of the planet which means that nights on Mercury are extremely cold. Enough about other planets - back to carbon on earth.

There are several systems that take up CO2 on the earth. Plants, for example, take CO2 from the air and make sugars by a process called photosynthesis. Light energy from the sun is converted into chemical energy, which the plant can use later to grow or reproduce. If this plant is eaten by humans, animals, or bacteria, then the carbon atoms that the plant took out of the air will be released as CO2 again when the organism uses the stored sugars to release energy. Plants take CO2 out of the atmosphere temporarily while they're alive and then release it back when as they're digested.

[By the way - when animals eat plants and then humans eat animals, very little of the original energy in the plant makes it to the human. This means it takes a lot of energy to feed animals to the point where they can be slaughtered and eaten. For more, check out Beef: Getting More than You Bargained For]

If the plant (or more commonly, little phytoplankton that live on the surface of the ocean) die, sink to the bottom of the ocean, and are preserved in the right way, then they can be transformed into a fossil fuel like crude oil over millions of years. This process of photosynthetic organisms taking CO2 out of the atmosphere and stores it for a long time. Over the past few 100 million years, a lot of CO2 was pulled out of the atmosphere and stored in the earth in the form of fossil fuel. Since they take so much time and energy to make, pockets of oil and coal are incredibly energy dense and useful to humans as a source of essentially free energy (if you think the price at the pump is expensive, imagine how much of your own time and energy it would cost you to push your car around wherever you went).

During the last century or two, humans have been finding and consuming a lot of fossil fuels to do useful work. Using all this energy releases the stored carbon that was taken out of the atmosphere a long time ago. The issue here is the shear scale of our carbon emissions. The graph below shows how CO2 levels have increased over the last 200 years since humans started burning a lot of fossil fuels. There’s a very clear upward trend over the last 150 years in CO2 levels in the atmosphere.

Note the clear increase in CO2 in the atmosphere since humans started using large amounts of fossil fuels in the industrial revolution. Click to enlarge. (NASA)

Note the clear increase in CO2 in the atmosphere since humans started using large amounts of fossil fuels in the industrial revolution. Click to enlarge. (NASA)

We are releasing carbon into the atmosphere faster than plants (and other carbon sinks) can pull it back out. This means that more and more CO2 is staying in the atmosphere – a fact that is warming the planet and contributing to climate change. The picture below is a simple diagram of the carbon cycle. The black labels and numbers shows the amount of carbon stored in various parts of the planet.

The deep oceans, for example, are the largest carbon sink, storing 38,100 gigatons of carbon. The purple arrows and numbers show how the carbon is moving around our planet. Humans release about 5.5 gigatons of carbon every year from fossil fuels alone. That’s about 40,300,000,000,000 pounds of CO2 a year, nearly enough gas to fill 1.8 Billion Goodyear blimps or cover the surface of the earth in CO2 filled ping-pong balls.

carbon_cycle_NASA

Carbon Cycle. Units are in gigatons of carbon (NASA)

As CO2 concentrations in the atmosphere get higher, the average temperature of the earth rises. As the earth’s temperature rises, the oceans become warmer. Cold water can store more dissolved CO2 than warmer water so the oceans release even more CO2 into the atmosphere as they warm up. [Have you ever opened a warm coke before and it made a huge mess all over yourself? That's because the CO2 that makes the coke fizzy was less soluble in the coke than if the coke had been cold]

Bottom Line: Who cares? You do – you just may not fully realize it yet. Currently, we’re releasing far more CO2 into the atmosphere than is being removed. 1.8 Billion Goodyear blimps filled with anything is a lot. The CO2 in the atmosphere will soon reach high enough levels to do serious permanent damage to the earth and its inhabitant (that includes humans). You wouldn’t give your child or grandchild a warm coke and let them deal with the sticky mess. So why would you give them a messy planet to clean up?

[Digg] [Facebook] [Reddit] [Twitter]
Posted in Climate Change, Energy, Greenhouse Gas Emissions | Tagged , | Comments closed

What’s a Locavore to do?

By ADC | Published: September 14, 2009
Eat local Lucy

Eat local Lucy

To start off with, I will define the term “locavore”. A locavore is intent on purchasing only (or as much as possible) locally produced food believing that minimizing food-miles (the distance food has to travel to your table) will in turn reduce energy consumption and save the planet. This belief has caught on in eco-conscious circles as well as in places like Europe, where country of origin labeling is increasingly popular on food. Though food-miles and the locavore mantra are simple to follow and seemingly a Geico caveman proof way of communicating the eco-merit of different food choices, these beliefs are seriously flawed both by practical standards and in their effectiveness. A number of recent popular and scientific articles have highlighted the complex interactions and secondary effects of eating local.

James McWilliams wrote two of the articles that caught my attention this week. In both articles (one published this week in Forbes and the other a year ago in the NYTimes) Mr. McWilliams disproves what he calls the “Locavore myth”. Practically, eating only food produced locally (perhaps in a 100 mile radius of your home) is near impossible. Unless, of course, you don’t mind forgoing fresh produce for the winter and enjoying only select fruits and vegetables that can grow in your local climate. A fully local diet may also mean forgoing a balanced diet. Mr. McWilliams also points out the difficulty (and political impossibility) of relocating people to areas fertile enough to provide local food year round (this would probably mean eliminating cities such as Phoenix and Las Vegas), as some may argue we need to do. Another problem with eating local (if we agree that people have the right to live wherever they please), is that producing food in some parts of the world requires more energy intensive inputs than food produced in another location.

A study found that imported New Zealand lamb required less energy to produce than local British lamb

A study found that imported New Zealand lamb required less energy to produce than local British lamb

Consider a 2006 study from Lincoln University in New Zealand, which found that a London shopper has less of an environmental impact by consuming lamb shipped from New Zealand than purchasing lamb raised in the UK. It turns out that New Zealand lambs enjoy plentiful pastures and travel by barge (which is one of the most energy efficient modes of transportation). In contrast, British lambs need feed to supplement the less plentiful greenery in the region thus emitting four times more carbon dioxide than their New Zealand counterparts during production. Unlike locavores, the New Zealand researchers quantify every input in the production of the final product, lamb. This approach gives us a complete picture of the environmental impact of a given food choice, which locavores miss in their obsession over food-miles.

In short, there is no closing Pandora’s box. Now that we have become accustomed to fresh produce year round, know the health benefits of eating a well-balanced diet, and we have the technology to move food from more productive regions of the world to the less fertile ones, there is no turning back. In fact, as the New Zealand study and many others have proven, the environment may actually benefit from importing food versus producing it locally in some cases. So what’s a locavore to do?

In all of the confusing nutritional and environmental advice, one idea, above all, seems to be emphatically repeated: EAT LOCAL! The appeal of eating local lies in the simplicity of its mandate and its promise of undeniable environmental benefits. Because of its simplicity, food-miles make an excellent metric for communicating the environmental impact of food to busy consumers. In creating a new environmental metric for food, this simplicity should be preserved.

There are plans to label foods with bar codes or websites where the consumer can access environmental information about their food. Though this effort would help consumers understand the complicated web of resource and energy inputs in their meal, I’m afraid consumers will not have a sense of scale for understanding the information given and will not have the time (or interest) to look up the available information. Let’s face it, we usually go to the grocery store with far too little time to scan all of the salad green options and weigh each variable before purchasing.

Instead of measuring food miles, McWilliams suggests a compounded variable including all of the environmental effects of producing a food calculated from a full life cycle analysis. A compounded variable may pose some difficulties particularly in the analysis and expertise that would go into calculating the “food score”. Perhaps, another useful and simpler metric would be to calculate the energy consumed or greenhouse gas emissions (in CO2 equivalents) resultant from the production of a given food. Energy is an important metric because it quantifies the overall effort necessary to produce the food and thus would account for the energy for irrigation, agricultural chemical production, processing and transportation all of which have important environmental impacts. Likewise, greenhouse gas (GHG) emissions from the production of a given food product accounts for energy consumption and other environmental disturbances of food.  It would include emissions of potent GHGs from manure decomposition and nitrogen fertilizer application. Thus, the greater climate impact of non-fuel inputs of some products will be reflected in the food metric.

Whichever metric we chose to employ, we must also inform ourselves and the public as to the significance of the value. In January Tropicana reported that 3.75 lbs of CO2 equivalent are emitted in the production of a half-gallon carton of their orange juice. This is a fantastic conclusion except… that I have no idea what it means and neither did the NYTimes reporter that wrote about the result. To avoid confusion in the public, any metric reported on food should be scaled to a daily allowance to meet yearly CO2 emission targets, much like the percentage shown on nutrition labels. This seems simple enough, but is a crucial detail in getting the general public to understand and use food metrics.

Bottom Line: If locavores and the rest of us want to make better food decisions for ourselves and the environment we need to take a close look at the total impacts of producing food and define the variables that we consider most important. At a time when consumers are reeling from low-fat, low-carb and low-food mile advice any new eco-indicator for food needs to be concise and easily understood so that it doesn’t become just another nutritional fact on the label.

[Digg] [Facebook] [Reddit] [Twitter]
Posted in Agriculture, Energy, Food, Food miles, Greenhouse Gas Emissions, Human Behavior, NYTimes | Comments closed