Coming Soon: Plant-Based Roads

Plant-Derived Material Can Make Our Roads Carbon-Negative

With all the attention focused on shifting from fossil fuels to renewables, there has been less emphasis on the hundreds of other products made from petroleum and finding substitutes for them. Some of the more common commodities are plastics, shoes, lubricants, paints, sports equipment, synthetic fibers for clothing, and building materials, including roofing.

One ubiquitous product is bitumen, a fossil-fuel-derived binder that holds asphalt aggregate together. A company in Norway is recycling old, damaged roads by using a plant-based binder instead of bitumen. Currently, it has applied this process only to repairing roads. Because Norway is far north, its roads suffer from repeated freeze-thaw cycles. The non-petroleum bioasphaltic binder it employs is lignin — a wood-based material essential to creating structure for trees and plants. The company utilizes a machine called the Carbon Crusher to grind up the top layer of damaged roads before applying the lignin to rebind the ground-up aggregate into a new, durable top layer. 

Approximately 18 billion tons of asphalt make up U.S. roads. All these roads need to be maintained. Asphalt is energy- and resource-intensive, contributing substantially to climate change. Lignin, one of the most abundant natural polymers, is an ideal substitute for crude oil bitumen. Because trees capture CO2 as they grow, using lignin on roads sequesters carbon. This significantly shrinks the carbon impact, especially for road repair. When the road aggregate is recycled, as in Norway, the use of new material is avoided and their associated carbon emissions from production and transportation, often making the entire process carbon-negative.

The process of rehabilitating roads with lignin is faster, cheaper, and more durable than what has been the case with standard bitumen repairs. The biggest plus, however, is its environmental benefits. In Norway, they are finding that lignin is more flexible than bitumen, allowing the repaired surfaces to adapt better to the harsh weather, preventing cracks and making the repairs last longer.

Sweden and the Netherlands are also repairing roads with lignin. The process is starting to be applied to building new roads, but with fewer environmental advantages. The ultimate aim, however, is to stop building new roads — which incentivizes more driving — and focus on better care of existing highways.

It is critical that substitute products, processes, and technologies be found for the myriad of common petroleum-based products that dominate our modern life. What is now underway for asphalt is an instructive model.

Prefab Facades Make Old Buildings Carbon-Negative

Artificial Intelligence, Digitalization, and Robots Can Streamline the Retrofitting of Old Buildings

Globally, buildings use almost 30 percent of all energy for heating, cooling, and lighting. California is leading the world in requiring all new construction to approach zero net energy (ZNE). In a few years, this requirement will tighten even more. ZNE will become the minimum standard. But what about all the old, leaky, energy-guzzling buildings that constitute most structures in California, the U.S., and the world? The current pace of retrofitting — labor-intensive, customized, and on-site built — is projected to take more than 500 years to transform all structures. This will not do for a planet in crisis. The process needs to change. It needs to become digitalized, standardized, automated, streamlined, and industrialized. BlocPower, a U.S. company written about in a previous article, has moved a long way in this direction.

Ecoworks, a German company, has accelerated and standardized the process even more. Its first step uses artificial intelligence to find the buildings that consume the most energy. Once selected, each structure gets a 3D scan of its exterior and interior. This digital representation is turned into a detailed set of plans that includes new tailored façade panels with built-in insulation designed to fit like a glove onto the old building.

Once the digital drawings are complete, the plans are sent to an automated factory where robots build large panels (multi-story as needed) with windows, ventilation systems, and channels for utilities. Modular roofs are fabricated with integrated photovoltaic panels. Eighty percent of the work is done in the factory. It takes on-site workers about 20 minutes to install a panel, transforming an entire retrofit project into a few weeks rather than months or years using the traditional approach. Moreover, this schedule includes replacing all fossil-fuel equipment with efficient, renewable energy units. A recent retrofit went from using more than 500 kilowatt-hours per square yard of floor area to generating a surplus of electricity that gets fed into the grid.

Because the new building skin is attached to the existing structure, most of the old building is reused, creating a super-low carbon footprint for a project. At present, Ecoworks is doing multiple projects on similar buildings to scale up the process. While the current focus is mainly on apartment complexes, the company is looking to do schools and single-family homes next.

As the world seeks to reach net-zero carbon by 2050, Ecoworks is helping solve one of the biggest challenges of decarbonizing our built environment. As this approach comes to California and Santa Barbara, our review and permitting processes are going to have to become more streamlined and flexible.

Can Earthworms Solve the Water Scarcity Problem?

Nature Can Clean Our Polluted Water Efficiently and Inexpensively

Many farms, especially dairy farms, struggle with how to dispose of polluted wastewater. The hundreds of millions of gallons of water farms use gets contaminated with animal waste, artificial fertilizers, and harmful chemicals, which frequently percolate down to the groundwater that people could one day drink.

Some regenerative ag operations are finding a nifty solution to this problem. They are discovering that earthworms, those ubiquitous dirt-eaters, are also able to clean water. They have long been known as nature’s way of enriching soil, but only recently has it been found that they can also cleanse wastewater. 

BioFiltro, an international company, has installed more than 200 of their three-stage wastewater treatment systems. The first chamber contains wood chips, earthworms, and microbes. The second level filters the water through crushed rock, and finally the cleaned water is collected in a drainage basin. A dairy farm in Washington State pumps half a million gallons of manure and chemical-laden water through a BioFiltro vermifiltration unit each day. The worms devour all the manure and harmful chemicals while aerating the water and wood chips. The aeration by the worms prevents the chip layer from clogging and becoming anaerobic. The density of worms is around 12,000-18,000 per cubic yard. The dairy reuses this treated water 10 times.

Vermifiltrated water is highly nutritive, pathogen-free, and scrubbed of chemicals, qualifying it for use on crop fields. The key to this low-cost, efficient, and odor-free process is the earthworm. These workers live, on average, six years, have numerous offspring, and each one produces about 10 pounds of castings per year, a nutritious and valuable soil amendment. This vermicompost can produce an additional income stream for farmers or can be used on their own crops.

Traditional wastewater treatment is energy-intensive and generates around 5 percent of all greenhouse-gas emissions (GHG). In comparison, vermifiltration requires almost no electricity, thereby reducing GHG emissions by 91 percent. Astoundingly, earthworms remove more than 80 percent of nitrites in wastewater and reduce methane emissions by an even higher percentage.

Vermifiltration was recently approved to become a component of the California Department of Food and Agriculture’s Alternative Manure Management Program — a program that provides funding to farmers who install sustainable GHG-reducing systems.

Water is becoming an increasingly valuable and scarce resource. Climate change and droughts are further taxing the planet’s limited supplies of fresh water; 85 percent of fresh water is used in global agriculture. Vermifiltration offers great hope for cleaning, reusing and stretching our supply of water. It has even proven to be effective in treating industrial and municipal wastewater. Some scientists believe it to be one of the most promising efforts to stem the global water crisis.

A Win for Housing, Livability, and the Climate

California Is Starting to Reverse a Century of Policy That Has Shaped Our Cities

Cities across America have suffered from sprawl, degraded urban design, poor walkability, high housing costs, and economic injustice. Many factors contribute to these urban ills, but UCLA professor Donald Shoup makes a cogent case that parking requirements in zoning ordinances are the main culprit. Per professor Shoup, such mandates subsidize cars, thus leading to more driving and car ownership. Looking at numbers nationwide, there are eight parking spaces for every car.

A few weeks ago, Governor Gavin Newsom signed into law a bill eliminating parking mandates for residential and commercial developments located within half a mile of major transit stops. Cities in California (and elsewhere in the country) are facing a growing affordable-housing crisis. This legislation is an important win for housing and parking reform advocates, because parking requirements raise housing costs, eat up valuable land, and make communities less delightful places. This act to remove parking requirements is the first statewide effort to prioritize people and their housing needs over cars.

Starting a couple of decades ago, Santa Barbara began taking some tentative steps to reform parking mandates. Casa de las Fuentes on West Carrillo is a 42-unit, affordable rental complex, designed for downtown workers. Instead of the standard two parking spaces per unit, it innovated with just one and charged $50/month to any occupant who owns or has leased a car. Unbundling parking from condo or rental living spaces needs to be universal. Even with only one space per unit, the Casa’s covered parking is usually only half full.

Eliminating on-street parking reduces car trips, especially when accompanied by increased public transit. Copenhagen has removed 2-3 percent of its street parking each year for more than a decade with growing improvements to its economy and livability. In the past year, Oslo has removed more than 700 downtown parking places and replaced them with bike lanes, pocket parks, and sitting areas. Oslo’s ultimate goal is a total ban on cars in the city center. In Paris, the pandemic led to the mayor accelerating the plan to remove 72 percent of on-street parking and speed up the creation of more bike lanes.

California’s new parking reform law is not only helping with housing affordability and neighborhood livability but also reducing air pollution and greenhouse-gas emissions. As we move to more electric vehicles, it is still important to remove parking requirements and increase the fees charged for parking. Such changes lead to fewer vehicles being manufactured and the conserving of valuable finite resources. Moreover, fewer parking spaces mean cars are less dominant in urban design. Hopefully this California innovation will spread to other states, as often is the case when California takes the lead.