The Footprint of Air Travel

According to one carbon footprint calculator, a plane produces about 244 pounds of carbon dioxide each mile it flies. An average plane carries 218 passengers, so that's about 1 pound of carbon dioxide per passenger per mile in the air. To put this in perspective, this is actually much lower per passenger than for cars - but similar to trains. (2002 figures – average mpg – NOT a Prius). And, of course, to be a true count – one would need to factor in all the infrastructure costs… And, this is all dependent on the number of passengers, (both extra weight, and per passenger calculations), speed, wind, altitude….. So it is probably an exercise in futility to try to figure a complete comparison – but we can probably all agree that reducing the fuel, or at least the carbon footprint of the fuel, would be a good thing…

Airlines commit to Solena Fuel


No need to convince airlines of this - they have a strong financial motivation for reducing their fuel consumption. A decade ago, fuel accounted for about 15 percent of airline operating expenses. Today, it's 35 percent. Hence, the added fuel fee and the methodical slashing of any of the amenities, and thus all associated costs. Fortunately, out of necessity comes innovation.

At the recent Paris Air Show, nine major airlines committed to using Solena biofuels for their San Francisco based flights. While many so-called bio-fuels are primarily petroleum with a bit of corn added, this company is developing a zero emission fuel. I don’t profess to fully understand the technology – but I did note that they have commercialized the use of algae growth from recycled urban and agricultural wastes and a Plasma Gasification Vitrification process. Worth checking out their website.

KLM Royal Dutch Airlines says that in September, it will start using biokerosene derived from cooking oil for more than 200 flights on its Paris-Amsterdam route. Maybe they could fry up some food for the passengers in the process…. These are just some of the many industry initiatives to speed up the commercialization of aviation biofuels.
Another big factor has been the strong push within the airlines industry to “push beyond the cost,” implementing lean manufacturing at levels which rival that of Toyota. Perhaps because of the many constraints of cost, safety, and the very real connection between fuel use and weight, this industry has been at the forefront of the development of new materials and manufacturing technology. Now, with engine improvements for efficiency, the new generations of airlines may not look much different, but have made radical leaps forward in technology.

Southwest airlines was the catalyst to cause the industry to re-examine the assumptions of gate turn-around time and operations costs. By purchasing only one model of plane, they were also able to standardize all maintenance and supply chain activities. It seems that Frontier Airlines has employed much of the same strategy.

Future Vision - Airbus

The model of the hub-and-spoke operations seems very rooted in the mid century mass production mentality. Much as the power grid is re-assessing the possibilities of decentralized operations, so does there seem to be a move towards smaller planes. The 50-100 seaters are typically more fuel-efficient, are easier to fill up to capacity, and can have quicker turn-around times with curb-side baggage loading.

What does the future hold? Boeing completed the first test flight of a hydrogen fuel plane in 2008, PC-Aero has developed the ElektraOne electric light aircraft, powered by solar cells on the hangar roof. And faster flights (…. memories of the Concord). Yes, but will there be more legroom?

Energy Portfolio

In the financial world, there are certain nuggets of common sense which prevail, such as diversify, plan future income streams, keep a buffer in reserve. What if we were to image “energy” to be a similar medium of exchange? There are many similarities. Like cash, the reason we value “energy” (ie electricity, fuel) is for what it can “buy” - such as heat for water or cooking, hot and cold air for comfort.

Take diversification. Japan is experiencing first hand the problems which arise when one energy source is wiped out. In a country which imports 80% of its energy, nuclear power as seen as the solution, currently accounting for about 30% of the electricity, with planned for increases to 50% by year 2030. But that was before the March 11 earthquake and subsequent tsunami, which killed 24,000, contaminated area groundwater, and is an ongoing hazard even with the reactors capped in concrete. The resulting shortage of electricity has triggered a government ordered 15% cut in electricity use in the Tokyo and Tohuko regions to avoid blackouts. Prime Minister Naoto Kan has declared that Japan would abandon plans to build new nuclear reactors, saying his country needed to “start from scratch” in creating a new energy policy that should include greater reliance on renewable energy and conservation.

In our previous blog, we noted the example of Denmark, who was 98% dependent on petroleum imports, until the OPEC Crisis in 1973 prompted them to diversify their portfolio. Their plan included a short term switch to their own off-shore oil, and then - employing the second principle of planning future income streams - have been developing wind and solar energy sources.

Similarly, some countries have taken the Fukushima Daiichi disaster as a lesson to be learned. German derived 22% of its power from nuclear, but decided to temporarily shut down seven of the countries oldest reactors. All will be permanently taken off line by 2022. The country now faces the same potential blackouts this winter, but is prepared to support an accelerated development of wind farms and energy efficiency.

The current energy portifolio of the US is approximately 86% fossil fuels (40% petroleum, 23% coal, 23% natural gas), 8% nuclear, and around 7% from renewable energy. By comparison, California already sources 18% of its energy from renewable resources, and is targeting 33% by 2020- a doubling within less than 10 years. The voters supported this aggressive action toward clean energy with a 61% vote on Prop. 23 (Nov 2010 elections), which was a Texas Oil company backed effort to crush California’s landmark climate Bill.

The principle of buffering can be applied at the many levels. Nationally, these are similar to the federal monetary fund, and are the energy reserves, meant to cushion the blow of any individual source being disabled. However, utilities also build these into the system. Preventative measures, such as brownouts, are ways of triaging energy needs in a time of overload. Pro-active measures include demand side management with smart boxes to damper and delay demand for an overall smoothing of use.

Buffering can also extend to a building level. A building can be designed to optimize passive solar and wind, independent of power sources. However, as we learned in the early experiments of solar construction of the 70’s, relying on the sun alone is “putting all your eggs in one basket.” Another part of this passive survivability strategy is a design for minimal energy demand, which would include high levels of insulation as to be able to

maintain a comfortable temperature for many hours, or many days. And the final part of the energy portfolio is generated energy, which can be both site generated or purchased (ie imported) power. Even here, the building can have its own power buffer, with renewable power sources and a storage device – eventually electric car batteries.

Just as fiscal responsibility starts with the individual and extends to the government, so can a policy of energy responsibility be structured. Diversity, plan for the future, and build in a reserve. Will it be painful short term, for Japan, Germany, and California, as they diversify and invest in their future Yes, it will. But when they come out the other side of this, not only will they have survived, but like Denmark, they will be more stronger and more independent, less vulnerable to the fluctuation of fossil fuel prices. Even more important, these countries are investing in future energy technologies. In 2010, the “greentech”market was about $10 billion. By 2020 it is estimated to grow to $80 billion. This is the “golden goose” of the future. Seems like a worthwhile investment to me.

Concentrated Solar Power (CSP)

As a point of clarification in last weeks’ posting, the Desertec project is a solar project, but NOT photovoltaic collection. The technology is concentrated solar power (CSP), which uses carefully positioned mirrors to reflect and concentrate solar energy to boil a fluid medium that can activate a turbine. This works just like a coal steam power plant except that instead of coal, the heat source is solely concentrated solar power. The fluid is used in closed cycle regenerative system, much like a refrigerant system (refrigerator or A/C) with the heat activating the turbine or Stirling engine.

There are four types of concentrating technology currently in use. The parabolic trough is a reflector which is shaped in the inverse path of the sun, thus squeezing out maximum solar efficiency out of each solar ray. The Nevada Solar One plant near Boulder, Nevada uses this technology. The parent company, Acciona, suggests that an energy project utilizing concentrating solar power technology deployed over an area of approximately 100 x 100 miles in the Southwest U.S. could produce enough power for the entire U.S. annually. How is this so? Because the concentration ratio is 71:1, that is 71 times the sun power.

In North Africa, at sites near the coast, sea water may be used for cooling steam power cycle, which will be distilled in the process of being rendered to steam, thus providing desalination and providing much needed drinking water. For desert locations farther away from the coast, water-saving air cooling can be used to cool the fluid medium.

Another reflector technology is the Fresnel reflector commonly used in lighthouses, where the many thin reflectors enhance the light given off by a central source. For CSP, the light capture is the reverse, concentrating the solar rays on a single point.

The third reflector technology combines a parabolic reflector that concentrates light onto a receiver with a Stirling engine, thus eliminating the need to transfer the heat to a central boiler. While not as widely disseminated as the other technologies, this has the greatest potential as it has both the highest solar-to-electric efficiency among CSP technologies, but also can be scaled. Stirling engines were developed back in 1816 as a rival to steam engines. They are highly efficient, and can be designed to run on very small gradients of temperature differential. The technology is currently being explored in combined heat and power units (CHP), electric automobiles, heat pumps. My personal favorite is in the application of an independent residential energy generating plant called Cool Energy , whom I first reported on last summer, (see Ecobuildtrends 08-3-10), and who seem to be making steps toward commercialization.

The final concentrating technology used now is the solar power tower, which uses a wide array of reflectors to concentrate light on a single tower. The technical advantage is the ability to store heat in the saline working fluid, but it would seem that these might also offer an interesting aesthetic aspect, as an illuminated tower.

These Concentrated Solar Power Technologies are commercial operations, NOT sized for residential application. Also, the yield of energy per land mass and per investment for CSP is far greater than traditional PV. Something to keep in mind when creating financial incentives, or establishing policies for net-zero. It is often far more cost-effective and sustainable to purchase power from a renewable energy source than it is to generate it on site.  It may make more sense to offer incentives to building sites to reduce energy consumption, and use passive solar sources.

Our Energy Future

A much often cited statistic is that “within 6 hours, deserts receive more energy from the sun than humankind consumes within a year.” (Dr. Gerhard Knies). Of course, the masses of humankind don’t live in the desert. But energy can be transported, in the form of electricity. In fact, this is the driving motive for the Desertec Foundation, whose proposed €400 Billion (Euro) solar and wind generation parks in the Northern African deserts would produce electricity both for a the hosting countries and up to 17% of European power.

This project is technically well developed, with concentrating solar power systems, for maximum power generation, and conceptual design of a super grid of high-voltage DC cables. Even the electricity loss for the roughly 2500 km are only in the ranges of 6% (roughly the same distance as the Nevada desert to Chicago). At first glance, this all sounds feasible, but then one notices the original timelines of 2012 have been pushed back – with final completion dates listed closer to 2050.

The major obstacles identified by the project foundation are the political hurdles. The implementation of this massive grid system is based on the cooperation of countries / continent with histories more based on colonization vs. alliances, and puts Europe in a position of political dependency on North Africa and the Middle East, regions which have been and are currently experiencing civil unrest and inter-country strife. On the other hand, there could be an advantage to creating a closer interdependency between the regions, wherein both economies are strengthened. Besides, political unrest never stopped anyone from dealing with oil-producing countries.

This project is very bold in its ambition of size and geography. But not alone in concept. The availability of the sun is also being tapped in countries which can execute the entire project within the political borders, which allows the projects to proceed at a much faster pace. For example, Australia has just funded a 250 MW solar thermal/ gas hybrid plant in Queensland, and a second award to BP Solar (that would be the Beyond Petroleum BP) for another 150 MW PV plant in northern New South Wales. China is well under way in developing the Qaidam Basin, with plans of up to 12,400 KW production.   And there are the solar power plants in the US Mojave Desert, with a total of 354 MW.

What about the transmission lines, scarring the landscape and susceptible to terrorist attack? The Desertec venture is discussing placing these lines underground. Not such an impossible option - think Electricity Chunnel across the Mediterranean. But - does it make sense to tear up the desert with solar panels? Compare the photovoltaic potential in Italy of up to 100 GWh per square km, to a more than doubling of this potential in the North African Desert. The same investment in equipment can generate more than twice the power. While the panels do undoubtedly change the landscape, there is much to be said for the jobs created, the sustained energy and income, and in some cases – the side-benefit of potable water. Overall, the host countries would seem to benefit. The relative footprint is light, compared to oil exploration, mining, or the risks associated with nuclear plants.

And underlying all this is the reality of addressing the CO2 output, and preparing for the energy needs of the future. It requires very aggressive targeted government policies, public cooperation and initiative. For example, in addition to the 17% renewable energy import, Desertec proposes a EU energy mix with a drastic shift from crude oil, natural gas and coal (all CO2 producers) to almost 50% renewables in the EU, and no nuclear energy. This proposal addresses carbon output, future availability of fuel, as well as energy independence.

Is this overly ambitious? Maybe not, if one takes the example of Denmark, who used the 1970’s oil shortage as a wake-up call, and target 2050 to be totally fossil-fuel free (even weaning themselves from their own off-shore oil sources). There is no magic formula to their success, but it includes very strict building requirements combined with incentives, an approach of squeezing every bit of energy out of fuel sources (such as cogeneration plants), and a dedicated pursuit of renewable energy sources and technologies. Renewables already account for 23% of the energy, and oil use is less than 40%.

So while solar is part of the solution, it is not the only renewable energy source worth considering. Denmark is heavily investing in wind and exploring tidal surges. Iceland is tapping into its geothermal. Canada is drawing on the hydro-electric.

It can be done. Though this topic far exceeds the blog space, it is clear that sustainable energy independence isn't magic, and won't happen overnight. It is also clear that it will take vision, discipline, and dedication by citizenry and government, together. I've listened to one too many conversations blaming the government (for both too much and too little); other members of the A/E/C - or the public; lack of demand, cost, convenience, or even a cat... which had to have the A/C turned on high. Enough, already. Yes, WE can - as soon as WE start taking responsibility for our own role in the future.

Greening Canada's Housing Stock

There has been a lot of talk of should, woulds and coulds regarding the greening of the housing stock – but how are we doing? According to a recent Canadian Home Builders’ Association report, based on Natural Resources Canada (NRCan), 2010 data :” Energy Use and Greenhouse Gas Emission Performance in Canadian Homes Since 1990,” it would seem very well indeed. This report states that between 1990 and 2008, the total residential energy use increased by only 14.3%, compared to the 33% increase in the total number of household units, and a 45.5% increase in total floor area (Iarger homes). The report goes on to identify this good news to be a reflection in ongoing energy efficiency gains in existing housing, the effect of higher efficiency in new construction, and a number of other factors.

R-2000 Home Promotion

To give credit where it is due, Canada has been at the vanguard of pursuing energy efficient construction and should get a pat on the back for these results. Innovations in high performance building materials are often “inspired” by the harsher Canadian weather, and then eventually emigrate south across to the US marketplace. Canada also wisely tapped into the natural resources of water to provide “carbon-free” hydroelectric power, and have shifted more of their fuel requirements to this source, thus reducing their Green House Gas count even beyond the actual percentage of reduced energy consumption.

However, as a researcher, I couldn’t help but ponder a few of the data offered in this report. Is energy improvement over existing construction really a valid metric? This seems to be a moving target, and hard to compare. Yet, even measuring against an energy code is also a bit like a dog chasing its tail, as the code is constantly moving. Taking lessons from lean manufacturing, what if we were to evaluate the houses to net zero HVAC load, which is essentially the “perfect” scenario for energy efficiency? This makes the measurement baseline the same for all houses, and is scaled to the square foot of the house? One can assume that very few houses would achieve this (it would also allow for off-site energy from zero carbon sources – such as hydroelectric), but this approach would both tell us how bad the old energy hogs are, as well as where the state of the art is today. It could be compared across all nations.

Another number which I found interesting was the ratio of homes removed – ie demolished - relative to those built. In Canada, in the time frame of 1990 to 2008 that ratio was four new homes built for each one demolished. This was an average number, with Ontario, Quebec and Alberta removing only a 9% of the old stock, and the rest of the provinces in the 20% and above. A quick dig for comparison data in the US found a census document with a similar timeframe of 1980 – 2005, with a ratio just over 3 houses built for each one destroyed (adjusted for mobile homes – which don’t seem to be as prevalent in Canada – a bit chilly eh?) Many questions spring to mind. Why the US is demolishing more houses, relative to those built (almost 30%)? Does the weather allow for more cheaply built construction which then doesn’t last as long? More termites? More natural disasters? And why were the three provinces so low relative to the others? City vs rural? Housing stock materials? Need? Age?

Speaking of age, of the Canadian houses demolished, 9.3% were only about 10 years old when they were demolished by 1990, and another 10% were less than 20-30 years old. So, we are demolishing about 20% of the houses before they reach the end of their 30 year mortgage… And that is in Canada. I’ll have to dig a bit more to find the US numbers.

Which leads me to my final observation. In this report, Alberta led the country in terms of new housing, as a percentage of total housing stock, with nearly a 50% increase in the number of units, and yet achieved only a 6.5% improvement in the energy intensity of homes, less than half the national average improvement of 14.1%. Will there be 20% of those homes in Alberta torn down? Or more? How much potential energy could have been saved, both in operating energy and embodied energy, had these homes been built to a higher standard?

Again, let me stress that the report is a positive sign of steps in the right direction. But there is yet more work to be done, more questions to pose - and perhaps new ways of measuring which might inspire even greater improvements.

Real life “green” decisions

The first challenge in the adventure of my new apartment is the quandary of the wood floor. Unlike the main floor, which is a nice quartersawn oak, this upper floor is some sort of Southern pine. Wide board, very soft, tends to just flake off and cause horrendous slivers. The floor is quite uneven, and boards are also somewhat warbly. What are the possible courses of action?

The criteria from the landlord’s side are cost, durability and ability to clean up after tenants. The renter wants clean, no slivers and preferably a nice looking floor. Keeping the existing condition is the least expensive, the floor can be somewhat cleaned, but it splinters something awful and looks terrible. Option 1 might be cheap carpet, but this is a problem keeping clean in a rental. Option 2 is tearing it up and putting down a new subfloor and floor, but this is definitely more expensive, and would probably have ended up in a laminate floating floor. My experience with putting shiny new plasticky floor finishes down is that they make everything else look old and grungy. Putting down an expensive wood floor does not make good economic sense from a landlord’s standpoint. Floating a floor over the existing floor would also not work, since the surface is far from level.

The solution, find a renter who is suffering from handy(wo)man withdrawal syndrome, and just craving to do some work. Make sure this person has a strong sense of self-identify in her surroundings, and is wanting to put her personal imprint on the place – and voila – you have all the dedicated labor you need to rehab the current wood floor. A little horse-trading of labor for rent, and the deal is arranged.

Having resolved the economics, the next question is that of practicality, and durability. Practicality would dictate a quick coat of polyurethane, knowing that the rapid relative humidity changes in this climate would probably play havoc with the floor finish. But it would be done in a day or so. Still looking grungy, but shiningly so.

Fortunately, this same renter has no sense of practicality but a strong sense of aesthetics and dedication to durability, and thus has lovingly rehabilitated the floor. Sanding to remove the layers of grunge and patina, patching to fill in the many, many gouges and holes, linseed oil to nourish and harden the wood fiber, a sanding sealer resin to provide a stronger top surface, and finally, a top lacquer coat. Yes, it took a full week for the extra time for the oil to penetrate and cure, but it was well worth it. The floor is gorgeous and good for another 100 years…. Both renter and landlord are happy.

Is this the recommended solution in all cases? No, but the point of the story is that there are many perpectives of involved stakeholders, several "green" criteria to consider, and many options. "Greenness" is a result of choices made based on situations. This was our reality, and hence our solution.