Glossary

Fuels used in place of conventional fossil fuels such as diesel, petrol or heavy fuel oil. In shipping, the main options include methanol, ammonia, hydrogen, biofuels and liquefied natural gas, each with different costs, infrastructure needs and emissions.

A compound of nitrogen and hydrogen, widely used to make fertiliser. It is being developed as a shipping fuel because it contains no carbon, although it is toxic and needs careful handling.

A biological process in which microbes break down organic material without oxygen, producing biogas and a residue called digestate. It is widely used for food and farm waste.

A unit of pressure. One bar is roughly the pressure of the air around us at sea level, so 221 bar is around 221 times normal atmospheric pressure.

A process that treats a set quantity of material at a time, in repeated cycles, rather than as a continuous flow. RiPR uses a batch-based design.

Methanol made from biogenic sources such as waste or biomass. The biomethane, hydrogen and captured carbon dioxide from RiPR are key primary feedstocks in the production of bio-methanol for shipping.

A stable, carbon-rich solid, similar in appearance to charcoal. It can be used to improve soils and can hold carbon out of the atmosphere for long periods.

A raw mixture of mainly methane and carbon dioxide, usually produced by anaerobic digestion. It can be upgraded into biomethane by removing the carbon dioxide and impurities.

Carbon that plants absorbed from the atmosphere as they grew, as opposed to fossil carbon that has been locked underground for millions of years.

Hydrogen produced from biomass or organic waste rather than from fossil fuels or electrolysis. The hydrogen from RiPR is biogenic.

Organic material from plants and animals, including crops, wood, agricultural residues and some wastes, that can be used to produce energy.

Methane produced from biogenic sources, such as organic waste, and cleaned to the same quality as natural gas. It can be injected into the gas grid or used as a fuel, replacing fossil gas without changes to boilers, engines or pipes.

Supplying fuel to ships, whether in port or at sea.

Removing more carbon dioxide from the atmosphere than is emitted across a product’s whole life cycle.

Separating carbon dioxide so that it is not released into the atmosphere, either to be stored permanently or used to make other products. RiPR produces a separate stream of captured carbon dioxide.

A common unit for comparing the climate impact of different greenhouse gases, by expressing each as the amount of carbon dioxide that would have the same warming effect.

Where the carbon dioxide emitted by an activity is balanced by the same amount being removed or offset, giving an overall impact of zero.

An approach that keeps materials in use for as long as possible and turns what would have been waste into a resource.

Short for clean technology: products and services that reduce environmental impact, such as low-carbon energy and waste treatment.

Generating electricity and useful heat at the same time from a single fuel source, making better use of the energy in that fuel.

The first plant built at commercial scale, used to prove that a technology performs reliably and economically in real operation.

A UK technology innovation centre and part of the High Value Manufacturing Catapult. We have partnered with CPI multiple times and they have also carried out an independent assessment of our RiPR technology.

The temperature and pressure above which a substance no longer has separate liquid and gas phases. For water, the critical point is 374°C and 221 bar.

Reducing or removing the carbon dioxide emissions from an activity, such as heating, power, transport or industry.

Businesses built on significant scientific or engineering advances, which often take longer and more investment to bring to market.

Digestate is the nutrient-rich material that remains after organic feedstock, such as manure, food waste, or crop residues, has been broken down in an anaerobic digestion process to produce biogas.

An engine that can run on two different fuels, for example methanol and conventional marine fuel, giving ship operators flexibility while supplies of alternative fuels grow.

Synthetic fuels, such as e-methanol, made using hydrogen from electrolysis powered by renewable electricity. Equisera uses the term bio-methanol because the gases from RiPR comes from waste rather than electrolysis.

Using electricity to split water into hydrogen and oxygen.

Recovering energy from waste, most often by burning it in an incinerator to generate electricity and heat.

A UK government scheme that offers tax reliefs to individuals who invest in qualifying early-stage companies. Tax treatment depends on individual circumstances and may change.

The public body responsible for protecting and improving the environment in England, including regulating waste and issuing environmental permits.

A permit from the Environment Agency that sets conditions for activities that could harm the environment, such as treating waste.

Ownership in a company, usually held as shares.

Raising investment from a large number of people, usually through an online platform, in exchange for shares in the company.

The detailed engineering stage that defines a plant’s design, costs and schedule before construction. A pre-FEED study comes first and tests the options at a higher level.

The raw material that goes into a process. For RiPR, the feedstock is wet biogenic waste.

The point at which a project’s backers formally commit the money to build it.

Able to compete on price with the fossil fuels a product replaces. Equisera’s aim is for RiPR to deliver low-carbon gases at fossil-competitive prices.

A European Union regulation, in force since 2025, that requires larger ships calling at EU ports to steadily reduce the greenhouse gas intensity of the energy they use.

Feeding gas, such as biomethane, into the existing gas network so it can be used by homes and businesses in the same way as natural gas.

A conventional thermal process that converts carbon-based material into gas at high temperatures with a limited supply of oxygen. Wet materials usually need to be dried first. It is a different process from supercritical water reforming, which Equisera uses.

The charge a waste producer pays to a facility to accept and treat its waste.

A general term for low-carbon gases, such as biomethane and hydrogen, that can replace fossil natural gas.

Gases that trap heat in the atmosphere, including carbon dioxide, methane and nitrous oxide. Methane is far more potent than carbon dioxide over the short term, which is why stopping it escaping from rotting waste matters.

The lightest element and a clean-burning fuel that produces only water when used. Most hydrogen today is made from fossil gas, but it can also be made from water using electricity, or from biomass and waste.

Shorthand for how hydrogen is made. Grey hydrogen comes from natural gas with the carbon dioxide released. Blue hydrogen comes from natural gas with the carbon dioxide captured. Green hydrogen is made by electrolysis using renewable electricity.

The United Nations agency that regulates international shipping. It has set a goal of net zero greenhouse gas emissions from international shipping by or around 2050.

The UK’s national innovation agency, which funds and supports businesses developing new technologies. It is part of UK Research and Innovation.

A UK tax charged per tonne of waste sent to landfill, designed to encourage alternatives.

A document, usually non-binding, setting out two parties’ intention to work together or agree a deal in future.

A method for measuring the environmental impact of a product across its whole life, from raw materials and production through to use and disposal.

Natural gas cooled to around minus 162°C so that it becomes a liquid, making it easier to store and transport. It is used as a shipping fuel and produces fewer emissions than oil-based fuels, but it is still a fossil fuel.

A unit of power equal to one million watts, often used to describe the size or output of an energy plant.

A non-binding agreement setting out how two or more organisations intend to work together.

A simple liquid alcohol used to make chemicals and plastics, and increasingly used as a lower-carbon fuel for shipping. It is made by combining hydrogen with carbon dioxide or carbon monoxide.

The chemical process used to make methanol, in which hydrogen is combined with carbon dioxide or carbon monoxide over a catalyst at high pressure. The hydrogen and captured carbon dioxide from RiPR can be fed into methanol synthesis to produce bio-methanol.

A fossil fuel made up mainly of methane, used for heating, cooking, power generation and industry.

Reducing greenhouse gas emissions as far as possible and balancing any that remain with removals. The UK has a legally binding target to reach net zero by 2050.

An agreement by a buyer to purchase some or all of a project’s future output, such as fuel or gas.

The regulator for Great Britain’s gas and electricity markets.

A legal right that stops others from making or using an invention without permission for a set period. RiPR has a granted UK patent, an allowed European patent and further applications pending in other countries.

A small-scale plant used to test a process under realistic conditions before building at commercial scale.

Approval from the local planning authority to build a new development or change how land or buildings are used.

A mix of chicken manure and bedding material, such as wood shavings or straw, produced in large quantities by poultry farms.

An early working version of a technology, built to test and improve the design.

A chemical process that rearranges the molecules in a material to produce useful gases, most commonly hydrogen.

Equisera’s patented system for turning wet biogenic waste into useful products. It uses supercritical water reforming to produce biomethane, hydrogen, captured carbon dioxide and biochar, and is designed to work with infrastructure that sites already have.

Moving a technology from laboratory or pilot size to larger commercial sizes.

A standard way for organisations to report emissions. Scope 1 covers direct emissions, Scope 2 covers purchased energy, and Scope 3 covers everything else in the value chain, such as suppliers and waste.

An early stage of investment that helps a young company develop its product and prove its market.

Typically a company’s first major round of investment from venture capital funds, used to scale up after early progress.

The semi-solid material left over after wastewater is treated.

A smaller type of nuclear power station built from factory-made parts, designed to be quicker and cheaper to build than conventional nuclear plants. Not to be confused with steam methane reforming, which shares the same abbreviation.

A fuel made from processed non-hazardous waste, prepared to a set quality standard.

The most common way of making hydrogen today. Natural gas reacts with high-temperature steam to produce hydrogen and carbon dioxide. Without carbon capture, the result is grey hydrogen. Not to be confused with small modular reactors, which share the same abbreviation.

Water that has been heated and pressurised beyond its critical point, above 374°C and 221 bar. In this state it is neither a liquid nor a gas, and it becomes a powerful solvent that can break organic material down into simple molecules.

The process at the heart of RiPR. Organic waste is broken down in supercritical water into gases such as hydrogen, methane and carbon dioxide. Because water is part of the process, wet waste does not need to be dried first, which saves time and energy.

A scale from 1 to 9 describing how mature a technology is, from basic research (TRL1) to proven in full commercial operation (TRL9). RiPR is at TRL6, meaning it has been demonstrated in a relevant environment.

The order of preference for managing waste: prevention first, then reuse, recycling, other recovery (such as energy), and disposal only as a last resort.

Organic waste with a high water content, such as food waste, sewage sludge, animal manure and poultry litter. It is often difficult and costly to treat because it usually needs drying first.