Charting the course: many roads could lead us to successful sustainable energy development in...

The implementation of the principles underlying the development of sustainable energy presents an enormous challenge. The Brundtland definition of sustainable development can be directly applied to the field of energy; to quote, "Development which meets the needs of the present, without compromising

the ability of future generations to meet their own needs." This encompasses the full implications of how we supply and use energy, and the impact on the environment and health. The goal is to avoid damaging the natural ecosystem so that future generations are able to live in a healthy, clean, and pleasing environment.

At present, the signs that monitor progress towards sustainable development are not all positive. The International Energy Agency (IEA) has taken a look ahead over the next 25 years to 2030, projecting energy demand and the implications of meeting that demand using today's approaches and technologies. The messages give us reason to pause--world energy demand will continue its inexorable growth, and fossil fuels will account for almost 90 percent of the world's increased demand for energy between now and 2030. The impact on the environment, measured in terms of energy-related greenhouse gas (GHG) emission, is increasing in lock step, particularly, in countries in the midst of rapid economic development. Clearly, as the IEA has stated, this is not the making of a sustainable energy future.

Routes to sustainable development

Faced with this situation, which route should we choose to lead us in a more sustainable direction? There are three general actions to consider that have universal application for the world's economies.

First, we need to start by reducing the overall amount of energy we use in our daily activities, in transportation, in industry. Think of this as "conservation" of the energy we have at our disposal by reducing the amount we use.

Secondly, we need to use energy efficiently. In industry, this means paying careful attention to bow the generation of electricity and heat can be done through cogeneration, how heat can be captured and re-used from each stage of a petrochemical process, how exothermic reactions can supply heat for parallel processes. Great gains have been made in these areas by industry as energy costs have become more apparent on the bottom line. But much more can be done, particularly in the design and engineering of new energy-efficient equipment. And, a more exciting route with higher potential would be a thorough, full-cycle re-analysis from first principles of the fundamental approach being used. Could we use biotechnology in some part of an industrial process, such as using bio-materials as a source of carbon for making steel?

Thirdly, ways need to be found and applied, soon, to reduce the impact of our energy activities on the environmental ecosystem around us, and globally. For example, for looking at the GHG emissions side of a sustainable equation, we need to look seriously at how we can reduce the amounts of carbon released into the ecosystem. This means making the best use of emerging renewable energy technologies. For example, wind energy is currently the fastest growing renewable energy supply source as turbines become larger, and as wind farms become integrated into the power grid. It also means reducing the emissions from the use of fossil fuels to near zero, making the long-term sustainable use of coal and natural gas a viable pathway both for developed and rapidly growing economies. It means looking at new transportation fuels (such as ethanol and biodiesel) after carefully assessing their life cycles, to help reduce the emissions from the transportation sector.

So, while the challenges of moving towards a sustainable energy future are many, there are promising routes that head in the right direction. They include a combination of both "transformative technologies," and more importantly, "transformative behaviour," on the part of industry and each of us.

Potential of energy technology

Although there is no single quick solution to achieving sustainable development, new approaches to energy supply, conversion, and end-use through innovative energy technologies offer great potential. Technology can be applied to improve energy efficiency overall, to find new fundamentally different ways to provide energy services in a fully sustainable manner, and to reduce environmental impact to a significant degree.

The federal government's approach to finding new energy technology solutions programs is carried out and managed at Natural Resources Canada (NRCan). This approach has three key features. The first is to look at energy systems rather than individual energy technologies isolated from the system they operate in. We begin by applying "system thinking" to how energy can be supplied, captured, re-used, and how waste heat and by-products can be economically exploited further down the line. Next, we will consider the full-cycle impact of the technology, from the source of the energy in one form, through its use, and also to the by-products and waste produced. Lastly, we take the future into account by investing in research dollars in new ideas and innovative "transformational" technologies.

Examples from our current R&D portfolio will serve to illustrate how we are developing technology aiming to move towards a more sustainable energy future. The following three examples use new innovative approaches and are selected from the supply, conversion, and end-use of energy. From the perspective of sustainable development of energy, they address: the benefits of considering the full life-cycle of a new technology or process; the use of a currently overlooked source of energy; and considering the potential environmental impact arising from capitalizing on a new source of natural gas.

1. Cellulosic ethanol--transportation sector

Ethanol-based biofuels are seen as attractive alternatives to today's fuels. Recognizing that transportation demand is growing the most rapidly amongst the end-use sectors, concomitant with a corresponding increase in emissions, it is important to develop and put new technology into action.

The traditional approach is the grain-sugar-ethanol process that supplies all of the ethanol used in the transportation sector today. Looking at this process from a sustainability standpoint, the net energy balance of the multi-step process of tilling-seeding-fertilizing-harvesting-processing is believed to be positive overall. The growth in demand for grain to feed the many new ethanol plants is certainly a boost for the agricultural community.

An attractive alternative is a "second generation" approach that offers apparent sustainability benefits based on cellulosic conversion of waste biomass to ethanol. The feedstock can be cereal straw on cornstover. The process involves the conversion of ethanol by carrying out a pretreatment process to open up the surface of the fibre, followed by enzymatic hydrolysis of the cellulose using cellulase made at the plant. The hydrolyzate sugars are fermented to ethanol by yeast, and the ethanol is recovered by distillation.

Lifecycle accounting indicates a positive energy and environmental balance. This technology enables the productive use of waste biomass from a variety of sources.

This approach has been successfully developed and piloted in Canada by IOGEN Corporation. The next critical step is a full-scale operation.

2. CH4MIN--energy from dilute methane in mine ventilation air

This example illustrates a step towards sustainable development by exploiting an overlooked source of energy.

The ventilation air from many subsurface coal mines contains trace amounts of methane. It is liberated from the coal measures by the mining and extraction process and is responsible for 250 million tons of C[O.sub.2] equivalent per year, worldwide. The "warming potential" of the CH4 molecule in the atmosphere is 21 times larger than C[O.sub.2], underlying the environmental benefit of capturing and using this methane.

A technology has been developed by Natural Resources Canada to oxidize the low concentration methane in air in order to capture the energy value of the methane.

The CH4MIN technology operates in a flow reversal mode to maintain a steady reaction temperature without external heat. It does this by using part of the exothermic heat of reaction while the other part is used for useful work. The heart of the technology is a catalyst that reduces the auto-ignition temperature of methane by several hundred degrees (i.e., to as low as 400[degrees]C). Such a low temperature operation does not generate NOx (another greenhouse gas) and eliminates the use of costly high temperature materials). The methane oxidation process releases heat that can be harnessed to produce environmentally friendly energy. The heat produced is captured by the heat exchanger for local applications.

One industrial CH4MIN reactor will reduce GHG emissions by 115 KT C[O.sub.2] equiv/ yr and produce about 200,000 GJ/yr of thermal energy. Assuming a 50 percent penetration rate, preliminary evaluations show a potential of 450 CH4MIN units in China and over 500 units in the rest of the world. An economic assessment done in 2000 showed that the cost of producing one GJ of thermal energy with the CH4MIN technology is US$1.97 without C[O.sub.2] credits and US$1.15 with a C[O.sub.2] credit of US$1.50 per tonne of avoided C[O.sub.2].

3. Gas hydrates, long-term supply of natural gas, studying environmental impact

The world economy will remain dependent on fossil fuels for many years to come. It is essential to find new sources of natural gas--the cleanest burning fossil fuel. This example illustrates the need for long-term thinking about new sources of energy and careful consideration of the potential environmental impact arising from their exploitation.

Natural gas hydrates are in a stable form of ice-bonded sediments containing methanol in two configurations. They are found within and under permafrost in polar environments, and in deep marine sediments at and below the sea floor adjacent to the continental shelves of most continents. The storage capacity of this form of solid-state gas storage is impressive--160 times more gas per volume than conventional reservoirs in Western Canada.

Research work to date has resulted in excellent characterization of the resource in the permafrost beneath Canada's Mackenzie Delta and encouraging results from a brief production experiment in 2004.

Three approaches to future commercial production are being examined--regasification through depressurization, liberating the gas through heating, and chemical transformation. At present, most of the attention is directed to depressurization methods.

From a sustainable development perspective, plans for full-scale exploitation will consider the overall energy balance of the production method, and also the impact on the fragile sensitive local Arctic environment. It is important to minimize the "footprint" of production operations, and to investigate the possibility of disturbing the upper zones of permafrost through warming, or the possibility of collapse or subsidence from destabilization as a result of melting the base of the permafrost zone below. These aspects will be considered carefully by scientists during the next experiment that involves a longer-period production test.

In closing, sustainable development in energy is an area of opportunity for Canada. Canada has all the ingredients needed to be a world leader in clean energy, given our rich and diverse resources, our energy-intensive economy, and an innovative approach to technology solutions. The key ingredients combine an examination of preferable approaches to today's current technologies--technologies that are sustainable and more economical--and considerations of the full-cycle from supply through conversion and on to end-use. Equally important is a good understanding of the economic and social drivers that will determine the ultimate success of these technologies.

Each stakeholder has a role to play in moving towards a sustainable energy future. University researchers are at the leading edge of new concepts and the earliest explorations through basic research. Government scientists can take the lead in conceiving and researching new applications and pathways. Industry has the opportunity to participate in the exploratory phases through partnerships with universities and government researchers from the outset. Ultimately, companies will be the lead agents for full-scale demonstrations and widespread end-use.

Meeting the world's increasing appetite for energy services in a fully sustainable fashion is indeed a significant challenge, and energy technology offers many promising solutions.

Graham R. Campbell is director general of the Office of Energy Research and Development at Natural Resources Canada. He is chair of the International Energy Agency's Committee on Energy Research and Technology (CERT), and a member of several R&D advisory boards.