Landfill gas for dinner: Is methane-made protein the future of food?

Problem: Landfills and sewage plants produce methane, which is a greenhouse gas and contributor to climate change. At the same time, the world’s demand for food, especially those high in protein, is soaring.

  • Two companies – Calysta Inc. (CA, USA) and String Bio (India) have independently discovered processes for converting landfill biogas to protein.
  • Methanotrophic soil bacteria ferments the methane to protein in a water-based solution, which can be dried into an edible powder.
  • The protein is currently added to animal feed, whilst human consumption trials are planned pending further purification.
  • The product can be used as a fish-meal replacement, which is currently sourced from wild commercially-caught fish, the populations of which are under immense pressure from over-fishing.
  • StringBio aims to commercialize these systems to a domestic level for community waste-to-protein initiatives.


Bloomberg Technology: Landfill Gas for Dinner? Scientists to Cook Food From Waste (September 26, 2017)

Stakeholders interested in this technology:

  • Landfill / biogas plants / any other methane producing industrial processes
    • Plant operators
    • Waste management
  • Animal feed agribusinesses and high-protein food retailers
    • Investment team
    • Procurement and supply chain

Steps for deployment:

  1. Measure methane levels at production facility for feasibility
  2. Install methane-capture technology
  3. Send to relevant conversion company (ie. Calysta Inc.) for processing


Creating new products out of food waste


Sustainability Problem: Waste management – 40% of US food supply ends up in the trash.

Technology: Providing data, transparency, and hardware for “upcycling” or reducing food waste. These types of products can include those that link wholesalers with food that may go to waste soon with restaurants at a significant discount OR provide hardware or services to generate fertilizer, animal feed, or human food from food waste. More and more startups are emerging that create new products out of food waste, such as Back to the Roots which sells mushroom kits made from used coffee grounds and Wtrmln Wtr which sells watermelon juice made from melons which were un-sellable in grocery stores.

NY Times Article here

Stakeholders: Consumers, Manufacturers, Grocers, Farmers, Wholesalers, Restaurants

Implementation: (1) Identify points of major food waste (from manufacturers, grocers, consumers, etc. and analyze data to understand and prioritize biggest areas of waste to focus (2) Partner with providers and consumers of identified area of food waste to pilot process and technology for one location (3) Scale with existing partners to additional locations or manufacturing plants

class june 16, 2016 – uni mst2135

Small Scale Waste-To-Energy (WTE)

Sustainability problem

Landfill sites in cities are filling up quickly. The quantity of waste is ever-growing with the increase of population, industrial and commercial activities. Energy prices are on the other hand going skyward. Many regions have additionally begun introducing ambitious renewable energy targets.Technologies to deal with waste that have by-products of energy, hence, are highly sought after.  The currently dominant waste-to-energy (WTE) technology is operated at a large scale. Images  of mass incinerators exerting gasses from large chimneys and traffic from convoys of wagons transporting waste does little to the industry’s reputation with the prevalent Not-In-My-Backyard (NIMBY) attitude.


Areas of sustainability

Waste, Energy, Pollution, Health.


Small-scale WTE plants tend to occupy 4 acres, in contrast to the average 20 acres required by mass burn incinerators. They are more affordable, have low profile construction and minimal emissions. They can thus be more easily integrated and presents a sustainable solution.  Although technological operators have varying small-scale WTE plant designs, the simplified explanation below will use that of ENERGOS ASA’s (a company based in Norway):


(1) Fuel preparation process – municipal waste is pre-treated through shredding and magnetically separating recyclable ferrous material.

(2) Thermal conversion process (from waste to energy) – First, fuel enters the primary chamber where it is gasified and syngas is created. Second, the syngas is transported to the secondary chamber for high temperature oxidation.

(3) Steam generation – Hot flue gas from the secondary chamber then gets recovered in the Heat Recovery Steam Generator, which consists of a smoke-tube boiler, water-tube boiler and economizer. The boiler system can be designated to deliver saturated steam (for heat) or superheat (for electricity production).

The system comes with a dry flue-gas cleaning system where lime and activated carbon are injected downstream from the economizer, separating ash from flue gas hence controlling air pollution. 


Municipalities, Citizens, Technology Operators, Environmental NGOs, Investors


  • Municipalities need to be lobbied for the installation of small-scale WTE plants.They need to be exposed to successful implementation case studies.  NGOs may play a large part in providing assistance for such lobbying efforts.
  • Local communities in areas with potential installation of small-scale WTE plants need to be educated regarding its benefits (especially in comparison to the larger scale WTEs) in order to change their perspective.
  • Proponents of the technology needs to network and maintain good relations with investors in order to derive more funds for research and development to refine the existing small-scale WTE technologies.
  • As the technology can be useful not only by municipalities but also companies with large production of waste, governments should also provide market incentives.
  • Technology owners are expected to come up with financing options for municipalities that are interested in applying the technology.