Introduction

Fossil fuels are one of the main pollutants on the planet. The CO₂ emissions released by them are one of the main contributors to climate change. According to the Intergovernmental Panel on Climate Change (IPCC), in 2018, approximately 89% of global carbon dioxide (CO₂) emissions originated from fossil fuels and industry. [1]

Fossil fuels are formed from the decomposition of carbon-based organisms that lived millions of years ago, resulting in the creation of carbon-rich deposits. These deposits are then extracted and burned to produce energy. Crude oil or petroleum is a liquid fossil fuel created mostly by hydrocarbons. It can be found in underground reservoirs and, once extracted, is transported to refineries and transformed into usable fuels like gasoline. Another fossil fuel is coal,twhich is a carbon-rich sedimentary rock that can be extracted via underground or surface mining. In terms of emissions, it is the most carbon intensive fuel. Fracked natural gas, also known as shale gas, is a fossil fuel primarily composed of methane.

The impact of fossil fuels on our planet is far-reaching and severe. When fossil fuels emit CO₂, the heat is trapped in the atmosphere, producing an increment on temperatures. They also provoke ocean acidification, extreme weather, sea level rise, air pollution that causes health risks, water pollution, plastic pollution, and oil spills that can harm wildlife. In addition, fossil fuels are finite resources with a limited lifespan. These factors call for a need for change. [2]

Recognizing these challenges, efforts are underway to advance future energy technologies that prioritize energy efficiency, environmental sustainability, and economic viability. Even modest incremental enhancements to existing energy technologies can effectively address both the energy crisis and environmental challenges. As observed in the previous blog, the energy transition will be possible through a mix of renewable sources. One of these sources is alternative fuels, but what exactly are they?

According to the European Commission, alternative fuels are those fuels or power sources which serve, at least partly, as a substitute for fossil oil sources in the transport sector. [3]

Types of alternative fuels

In general, alternative fuels encompass all the fuels used for transport, excluding gasoline and diesel. Some of these alternative fuels can be used in current petrol engines without requiring any modifications. Their advantages include cleaner burning, producing lower CO2 emissions, and if they come from a renewable biomass source, the dependency on petroleum decreases. [3]

Let’s explore the six types of alternatives: electricity, hydrogen, biofuels, synthetic and paraffinic fuels, natural gas, liquified natural gas and liquified petroleum gas.

Electricity can be generated from three main sources: fossil carbon, nuclear energy and renewable sources.Currently, 39% of the electricity consumed come from fossil fuels, 35% from renewable energy and 26 % from nuclear energy. This indicates that electricity generation is reducing the consumption of fossil fuel by 61%. The main source of renewable energy is wind turbines. [4]

Hydrogen serves as an alternative for transportation and can be categorized into different types. Green Hydrogen is the most sustainable, often produced through electrolysis, where water is split into oxygen and hydrogen using renewable energy sources. Blue Hydrogen falls between sustainable and non-sustainable production, generated by reforming natural gas (a fossil fuel) but incorporating carbon capture and storage to mitigate its environmental impact. Brown Hydrogen, derived directly from fossil fuels without carbon capture processes, is not sustainable. [5]

Ammonia, a gas at room temperature and pressure, can be stored as a liquid at low temperatures. It is used in the maritime sector to replace some heavy fuels, offering safer storage than hydrogen and emitting less carbon than liquefied petroleum gas or compressed natural gas. [5]

Liquified petroleum gas is a low-carbon alternative, emitting 35% less CO₂ than coal and 12% less than oil. It increases resource efficiency in transport. Currently derived from crude oils and natural gas, it is expected to also come from biomass in the future. [5]

Biofuels like biodiesel, bioethanol and biomethanol are one of the most important types of alternative fuels, capable of reducing CO₂ emissions if sustainably produced and avoiding indirect land use change. Biodegradable and sourced from vegetable oils, animal fats and recycled restaurant grease, biofuels are produced using evolving technologies and can be used directly or blended with traditional fossil fuels.6 In particular, as a substitute of natural gas in several applications such as heating, electricity generation, and as a fuel for vehicles. Not only does it help reducing CO₂ emissions but it also fosters a circular economy by producing gas from different kinds of waste.

How does it relate to SEMPRE-BIO?

SEMPRE-BIO is set to enhance biomethane production by leveraging cutting-edge technologies. Our mission is to bridge the gap from models to reality within three European Biomethane Innovation Ecosystems (EBIE). These ecosystems incorporate five main innovative technologies, each optimized for different feedstocks:

1. Wastewater (CS1): We use electrolysis and biomethanation to convert wastewater into valuable biomethane.
2. Green waste (CS2): Our innovative approach combines pyrolysis and methanation to efficiently transform green waste into sustainable biomethane.
3. Manure organic waste (CS3): By utilizing cryo separation, we capture manure organic waste and create a renewable source for biomethane production.

These sources will be utilised to produce biomethane for public transportation, grid injection and local storage as bio-LNG.

SEMPRE-BIO’s ambitious goals align with the Horizon Europe call, aiming for four specific outcomes for a cleaner, more sustainable and secure energy supply, aiming for increased cost-effectiveness, diversified technology, market uptake and industrial-scale demonstrations.

Our discussion on alternative fuels underscores the crucial role of innovations like those implemented in the SEMPRE-BIO project in mitigating the environmental impact of traditional energy sources. Transitioning to alternative fuels not only addresses immediate environmental concerns but also enhances our long-term energy security. As these technologies develop and scale, their integration into our energy infrastructure is imperative for an effective energy shift.

[1] https://www.clientearth.org/latest/news/fossil-fuels-and-climate-change-the-facts/

[2] https://www.eesi.org/files/FactSheet_Fossil_Fuel_Externalities_2021.pdf

[3] https://alternative-fuels-observatory.ec.europa.eu/general-information/alternative-fuels

[4] https://alternative-fuels-observatory.ec.europa.eu/general-information/alternative-fuels

[5] https://stargatehydrogen.com/blog/types-of-hydrogen/

Author: Oria Pardo

Editorial: Lucía Salinas

Date: July, 2024