Sustainability | Renewable Energy

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21st-Century Sustainable Fuel Solutions

Replacing Petrol with Sustainable, Clean Energy Sources

Solutions to fossil fuelsThe negative externalities (pollution, public health/ environmental hazards, and the financial costs to repair damage to the environment and public health) from discovering, extracting, refining, and using oil, are extensive. Combustion of refined crude oil (gasoline and diesel, although diesel is more energy efficient) in vehicles has a significant negative impact on public health and the environment.

All kinds of environmental hazards and pollution stem from fossil fuels. Immediate dangers of burning fossil fuels are to the planet, in the form global warming and the dramatic increase of greenhouse gas emissions (GHGs) exacerbating climate change. Additionally, fossil fuel oil is a finite resource, a non-renewable natural resource, and is eventually going to be depleted, with no way to regenerate the fuel source. So, here are a few greener, sustainable alternatives to fuel transportation:

1st, 2nd, and 3rd Generation Biofuels

2nd and 3rd generation biofuels

Biofuels are produced from renewable sources. Biofuels (both ethanol and biodiesel) are commonly produced by individuals/ farmers, and both have industrially produced versions. Crops such as corn, sugarcane, and soybean represent 1st generation biofuel feedstocks. In addition, biofuel feedstocks include cellulosic plants (2nd generation biofuels), and algae (3rd generation biofuels). All of these feedstocks for biofuels are processed and used to create more efficient, more environmentally-friendly, alternative transportation fuels (ethanol and biodiesel).

Please see: 

Algae: the future of biofuel


Sources of cellulosic biofuel

Blending ethanol and biodiesel with traditional gasoline and traditional diesel produces a better fuel. It is possible to increase octane levels, decrease the quantity of GHGs discharged, and increase the fuel-efficiency of transit, using these alternative fuels. In the United States for example, gasoline contains at least 10% ethanol (E10) for the increased fuel-efficiency, octane levels, and environmental benefits of the biofuel blended fuel.

Vehicles that can run on biofuel blends (more substantial than just E10 or E15) are commonly known as hybrid vehicles. A hybrid vehicle can either be a hybrid that runs biofuels alone; or a hybrid that runs on a biofuel blend with gasoline or diesel. Other vehicles in the hybrid category include electric-biofuel vehicles, electric-gasoline vehicles, or a natural gas fueled hybrid (or even a hydrogen-fueled hybrid - see below). Hybrid vehicles designed to run on biofuels include an increasing global share of:

  • passenger automobiles,
  • buses,
  • light trucks,
  • heavy duty trucks for industry,
  • shipping vessels,
  • (and biofuel blends are even seeing some use on a small amount of airlines, as seen in this article).


A type of fuel growing in global use in vehicles, due to both its cost-efficiency and its fuel-efficiency, is biodiesel (another type of biofuel, in addition to ethanol). Biodiesel has both commonly produced, small-scale versions and industrially produced, large-scale versions. This type of fuel is made from animal and plant oils, lipids, and fats. Biodiesel is commonly sourced from plant-based cooking oils (mostly sourced from restaurant kitchens, or commercial plant-based oils produced on a large-scale basis for industrial biodiesel production purposes. Plant-based oils is the stock source with the largest share in the liquid mix making up this biofuel.

The plant-based oils are processed with an alcohol, such as methanol, and a catalyst, such as lye, (among other processes to make biodiesel from kitchen oil). The biodiesel is blended with traditional diesel (except for B100, which is entirely renewable), and then the biodiesel blend is used in modified engines. B100 is used to a significant extent in Brazil in public bus fleets.

Biodiesel is a cost-efficient and fuel-efficient alternative for cars, buses, trucks, ships, (and even planes). Biodiesel has industrial production processes which can be similar to the processes mentioned above, but on an industrial scale for large-scale production. Advanced biofuels use a next generation source, such as algae, as the main feedstock source for the biodiesel. Biodiesel results in an increase in fuel-efficiency, and a decrease in air pollutants relative to traditional diesel.

The most promising new source for the production of biodiesel is algae. Algae might just be the future of biofuel.

Biofuel Blends

A small level (5%, 10%, 15%) of ethanol or biodiesel can be blended with standard gasoline or diesel to make an efficient fuel blend with less environmental impact (this type of fuel blend is used in many countries worldwide). Just this relatively low level of a biofuel blend in fuels decreases air pollution from vehicles.

A blend of ethanol and traditional gasoline known as E85 - 85% ethanol and 15% gasoline, has gained popularity throughout the world (especially in Northern Europe). E85 (and B100) have significantly higher energy efficiency and lower environmental impacts (greater benefits are seen with B100). There are many grades of ethanol-based biofuel blends growing in use worldwide, such as E10, E15, and E85. There are also many grades of biodiesel blended fuels growing in global use - such as B5, B20, and B100 (B100 is not a blend, it's a 100% renewable source of fuel).

Hybrid vehicles (hybrid passenger cars, hybrid buses, hybrid light-duty trucks, hybrid heavy-duty trucks, hybrid ships) can be developed to run on numerous types of fuel and/ or electricity. Hybrid vehicles can run on biofuel and biofuel blends (either ethanol or biodiesel), liquefied natural gas (LNG), or compressed natural gas (CNG).

Often, hybrids run on two systems of fuel/ power, and at different times, such as biofuel-gasoline, gasoline-electricity, diesel-electricity, biofuel-electricity, and LNG-/ CNG-electricity. Motors/ engines in hybrid vehicles are designed to run on the most efficient fuel/ power source at the time (but many hybrids opt for the most efficient, greenest options), switching for brief times to internal combustion engines in the vehicle, when optimal.

Please see: Benefits of Hybrids, Plug-in Hybrids, and Electric Vehicles

Please also see: 10 Countries Advancing the Use of EVs

Electrifying transportation

Electric tram

Electric vehicles in widespread use throughout the world today on a mass commercial market basis include - light EV options, such as electric cars and light duty trucks; as well as light electric rapid transit and other electric mass transit options, such as electric and hybrid-electric buses.

Electric vehicles (EVs) are gaining in popularity throughout the world, as more and more countries are promoting the option of sustainable vehicles. EVs as public mass transit options in world cities, come in the form of buses and light rail (rapid transit light rail, tram, streetcar, trolley, or other light rail).

The commercial mass market of EVs is flooded with electric passenger cars, light-duty trucks, heavy-duty trucks, electric commuter rail, electric high speed rail, and as it is technically possible to electrify any type of transportation vehicle, electric vehicles can also be in the form of electric ships (such as the proposed hybrid-electric SeaBus ferries in Vancouver). Electric vehicles and plug-in hybrids work on battery power and are charged through an external electric source (see hybrids, plug-in hybrids, and electric vehicles).

These batteries can produce energy without combustion or pollution; however, they do require the creation of electricity from a utility, which is then sent to the municipal grid. The same is true for all electric mass transit in a city; electric transit options are only as green and clean as their electricity source. However, EVs do have the enormous environmental benefit of essentially eliminating GHG emissions and pollution from tailpipes. It remains a significant aspirational goal that the sources for the electrical generation used to power electric public mass transit options ideally are renewable energy sources, whenever possible.

Biofuels for aviation

Biofuel is used in transportation, including aviation and shipping on a substantial level; both as the primary fuel source for transportation vehicles (light/ heavy duty trucks, ships, airlines), and/ or as part of a biofuel-traditional fuel blend with gasoline and biofuel. Biofuel needs to be converted into liquefied natural gas (LNG) to be effectively used in the transportation sector. A couple of airlines in particular represent present use, and potentially expanded future use, of biofuel blends; and is the subject of this article from Bloomberg-

For years, airlines have experimented with biofuels, aiming to reduce both carbon emissions and their reliance on fossil fuels…several major carriers are planning larger-scale usage of biofuel in 2019 and 2020, including JetBlue Airways Corp.  United Continental Holdings Inc. said it would cut its carbon emissions by half [by using biofuels] compared to 2005 levels, by 2050, matching an industry target set by the International Air Transport Association.

United Eco-skiesUnited Eco-skies

United Airlines uses the most biofuel blends in their airplanes of any airline; after Jet Blue helped to pioneer the use of aviation biofuels; as detailed in an article by Fast Company. From this same Fast Company article ‘…biofuel blended jet fuel, with a carbon footprint smaller than regular jet fuel, but a comparable cost– is one way that the airline industry can begin to tackle its climate problem. By mid-century, like other industries, airlines will have to reach net zero emissions for the world to stay on track to meet the goals of the Paris climate agreement.”


A solution that's still mostly in the R&D/ demonstration phase is hydrogen; and hydrogen fuel cells are gaining in practical development for replacing transportation fuel in a few select cases, such as European buses. There are real world examples of hydrogen mass transit serving world cities today. The biggest hydrogen fuel cell projects in the Western hemisphere are Clean Hydrogen in European Cities (CHIC) and H2BusEurope, operating now in several countries throughout Europe. Hydrogen is also a promising future means for energy storage, and a variety of other industrial uses, however hydrogen still mostly remains in non-commercial R&D for now, as opposed to practical, real world applications.

Whatever the future of motoring, viable innovations have to continue to be researched, developed, and brought to the mass marketplace. Solutions to fossil fuels must continue to be explored and offered to the public sooner rather than later, for the good of humanity and the planet.

Please see:

Sustainable Mass Transportation

Please also see:   Biomass and biofuels

and   Clean Hydrogen in European Cities (CHIC) and H2BusEurope;

Vancouver - Alternative Transit Capital of North America

For real world examples of sustainable clean energy sources replacing fossil fuels in industries other than transportation, please see these articles on clean energy sources in the energy generation sector:

Renewable Energy: Solar PV & Solar Thermal

Renewable Energy: Wind & Offshore Wind

Renewable Energy: Hydroelectricity

Nuclear Energy - A Necessary Energy Source to Fight Climate Change

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