Ending Our Addiction to Natural Gas Will Not Be Easy

Addressing Climate Change Needs Workers, Investors, and Innovators to Be Involved

The Philadelphia Gas Works, founded in 1836, is the oldest gas utility in the country and still one of the most substantial with its 6000 miles of service lines and more than half a million customers. The nation’s largest gas utility is our SoCalGas Co. The reality, however, is that today all gas providers are facing existential threats from the quickening energy transition that aims to convert buildings from gas to electricity.

The gas industry has gained several decades of reprieve by promoting gas as the bridge fuel between coal and renewables. Nevertheless, as the urgency to address climate change has increased and the monitoring of methane leaks from gas pipes (three million miles of gas pipelines nationally) has revealed gas to be almost as dirty as coal, time is running out for gas.

Increasingly, cities’ climate action plans are targeting achieving carbon neutrality by 2050 or sooner. Banning gas from new construction is a relatively easy first step and will be policy in California in a few years. Much thornier is how to get gas out of existing buildings: Almost 60 percent of the country’s 120 million houses use natural gas.

The first step in a comprehensive approach to decarbonizing the nation’s energy infrastructure would be to improve energy efficiency in equipment and delivery systems and reduce consumption. The second would be to electrify as many cars, space heaters, water heaters, and cooktops as practical, using electricity from renewable sources. The third would be to replace as much natural gas as possible with low-carbon alternatives such as biogas, hydrogen, or synthetic gas (a liquid blend of hydrogen and ammonia or methanol designed for easy transport in existing pipelines), which combust without carbon emissions.

The gas infrastructure is old and in need of repair, but spending on pipeline maintenance above what is required for immediate safety is unwise. One strategy, beyond minimal repairs, is to select a neighborhood, convert it to a clean alternative, and then shut off that section of the gas system, thus reducing the size of the network. Another option is to develop a geothermal district. Ground-source heat pumps can tap temperatures deep underground to provide neighborhood heating and cooling. Installation costs are high, but operating costs are negligible. Gas line rights-of-way could be used for geothermal pipes.

The American Gas Association (and SoCalGas) has promised to use more biogas and create hydrogen/biogas blends. These cleaner alternatives need to be pursued, but costs are high, and scope appears to be limited to supplanting only a fraction of natural-gas use.

Reining in climate change requires many solutions. Gas utilities and the 98,000 workers employed in the gas industry need to be part of the picture. Repairing unsafe infrastructure, developing geothermal systems, and expanding renewable natural gas would use the expertise of many of these workers.

Large-Scale Carbon Sequestration Is Imperative

Combining Indigenous Wisdom, Research, and Technology Offers Carbon Storage to Scale

Nature has an uncanny ability to restore and regenerate itself. An area of forest the size of France has regrown across the world in the last 20 years with minimal or no input from humans. According to scientists, these restored forests have the potential to store more carbon dioxide than the emissions produced each year by the U.S. Despite this news, surprising to many scientists and conservationists, deforestation is still claiming vastly more forest than what is being regenerated.

Many have come to the realization that only through massive carbon sequestration will we be able to address climate change in time to keep the planet livable. One such program with a vision of large-scale carbon drawdown is called Seed the North. Located in northern British Columbia, it aims to regenerate large swaths of land, first in B.C. and then across Canada. The project’s mission incorporates three pillars: traditional Indigenous knowledge, scientific research, and harnessing the possibilities of technological innovation.

The impact of climate change can be seen in northern B.C., where forests are suffering from drought, wildfires, and pest infestations. These impacts are compounded by massive carbon unleashing through logging, mining, and fossil-fuel extraction — powerful industries in the province. Thousands of seedlings are planted every year by the forest industry but for economic value, creating fast-growing, high-yield monocultures.

Seed the North, enlisting local Indigenous communities for their knowledge of the land and as part of their workforce, collects biodiverse seedpods. When combined with biochar, made from the waste wood left behind by logging, these become biochar seed casings that optimize generation. The casings offer all the required nutrients and protect the bundles from drought and scavenging animals. With ecological diversity accorded highest consideration, many of the seeds in the bundles are not considered valuable to the forest industry but are essential to forest health, carbon reduction, and wildfire prevention. Seeds of deciduous trees (birch, alder, and Rocky Mountain maple) create fire breaks. In addition, their silvery leaves reflect the sun’s heat back into the atmosphere and provide nutrients while decomposing.

The final component, beside the biodiverse seed mixes and nutrient-rich biochar casings, is using drones to disseminate the packets. It is this ingenuity that has the potential for large-scale application. Initially, the project will target remote and hard-to-reach areas that otherwise would not be replanted. It will also focus on areas disturbed by natural events, like wildfires, floods, and landslides, as well as those impacted by industry.

Seed the North is working with the provincial government while also trying to forge links with private industry. The approach of incorporating Indigenous perspectives, increasing biodiversity, contributing to long-term carbon sequestration, and being able to go large-scale is holistic and unique. Once proven, this approach has applicability across the globe.

Concrete Is Changing

Bendable concrete is a big improvement to conventional concrete’s frequent failures. These failures lead to repeated infrastructure and building repairs, using enormous quantities of material and energy and producing large quantities of greenhouse gas emissions (GHG).

Engineered cementitious composites (ECC), the technical name for bendable concrete, gains its flexibility and durability from polyvinyl fibers covered with a thin (nano thick) slick coating that allows slipping rather than fracturing when placed under stress. As ECC is gaining acceptance, research and empirical evidence is demonstrating that the microfibers and surrounding microcracks make the concrete self-healing. When air and moisture migrate into the hairline cracks, self-generating reactions of carbon mineralization occur, binding the micro cracks together. Basically, calcium ions inside the cracked concrete combine with moisture and carbon dioxide from the air, creating a calcium carbonate material similar to sea shells.

For some decades, the concrete industry has been trying to reduce its carbon footprint. One of the most successful strategies has been substituting flyash, rice husks or silica fume ash for cement, the main culprit in concrete contributing to GHG. This substitution reduces carbon emissions by essentially the same proportion as the cement is reduced. Many mixes replace 50 percent or more of the cement yet yield a stronger concrete. Fortunately, these substitutions work well in ECC mixes, thus producing greater strength, less carbon emissions and flexibility.

Another promising development is adding micro-sized wax capsules to the concrete mix. The phase-change wax in these capsules shifts from solid to liquid, or the reverse, between 73-74 degrees and stores or releases a good deal of thermal energy in the process (as when water vaporizes into steam or solidifies into ice). This strategy has been successfully deployed in drywall for many years to dampen temperature swings, helping keep building interiors cool and comfortable. Changing phases can occur an indefinite number of times. When embedded in concrete these microscopic capsules can keep the inside of buildings cool in summer and warm in winter.

ECC is also being modified to neutralize pollutants, thereby acting as an agent to clean dirty air. Concrete is commonplace in urban environments; embedding nano-titanium particles in concrete converts certain pollutants common in smog into inert salts when in direct sunlight.

Flexible, durable concrete with self-healing, pollution-reducing, temperature-modulating properties offers a promising vision: an urban infrastructure that responds to environmental change to create a lower energy, healthier and more livable lifestyle.

Can Concrete Really be Bent?

As with many other products and processes, biomimicry (learning and imitating the processes of nature) is transforming the world of concrete. Although in the early stages of being applied, concrete that is bendable without fracturing is now a reality. Concrete is the most ubiquitous building material on the planet, but it contributes between 6-7 percent of greenhouse gases and is thus a major contributor to climate change. It has great compressive strength but, when it cures, it becomes a hard, brittle material.

The idea for bendable concrete is borrowed from nacre (mother of pearl), the material that lines the inside of abalone shells. The main material in nacre--small, hard bits derived from calcium carbonate--is made flexible by the natural elastic polymer that surrounds and ties these small chunks together. This combination makes nacre both strong and bendable.

A number of universities around the world, including the University of California at Irvine, Stanford and the University of Michigan have been investigating the nacre model for concrete. By eliminating the coarse aggregate from the mix (gravel, sand and cement) and adding microfibers of silica, glass, steel and/or polyvinyl, they approximate the flexibility of nacre. The interfaces between these tiny fibers and the cement recreate the controlled slippage in nacre. Bendable concrete, technically called engineered cementitious composite (ECC) is not a single design mix but a broad range of design mixes. The precision of these formulae comes from the application of micromechanics theory.

Essentially, the microfibers create many pre-calculated microcracks. This contrasts with conventional concrete that develops a few large cracks that permit water intrusion, degradation of the reinforcing steel and, consequently, early rupture and failure under stress. The fibers and accompanying microcracks allow ECC to deform without catastrophic failure.

The advantages of ECC concrete are numerous: lighter weight (40 percent less); 300 times more flexible; superior seismic performance; less frequent maintenance and repairs, thus saving on costs; no need for expansion/contraction joints (e.g., on roads and bridges); and faster curing (7 days compared to 28 days).

The disadvantages are higher cost, the need for more skilled labor, and getting structural engineers to specify it when they have been taught that concrete cannot be flexible.

There are recently built bridges in Japan, Korea and the US using ECC. A 60-story skyscraper using flexible concrete for superior seismic performance is currently under construction in Japan. When our roads and bridges, which badly need fixing, get rebuilt, they can have a much longer projected life by using bendable concrete. The significantly greater durability of flexible concrete is the biggest sustainable improvement. Less frequent rebuilding of concrete’s failures also means big reductions of greenhouse gases.