Balmoral anaerobic digestion tanks

Commentary - November 2021

Where are America's anaerobic digestion plants?


Why this question matters – for all our sakes

Here’s the good news: America has more than 2,000 anaerobic digestion (AD) plants operating across all 50 states.

They’re producing clean, environmentally friendly biogas that can be converted to renewable natural gas (RNG) to power millions of homes and businesses. They would otherwise have to rely on harmful and expensive fossil fuels for their energy.

AD-sourced RNG can also be converted to compressed natural gas (CNG) or liquefied natural gas (LNG) to power vehicles. Especially fleet vehicles that return to base for refuelling. CNG is so clean that it’s actually carbon negative.

Find out more about AD-sourced biogas here

So what’s the bad news? What’s the catch?

Environmentally, there isn’t one – anaerobic digestion really is the smartest way to deal with all the methane that’s harming the planet. Let’s put that methane to good use, generating clean, sustainable energy – instead of letting it escape into the atmosphere where it becomes a far more harmful greenhouse gas than carbon dioxide.

And commercially, AD makes excellent business sense too. It offers a surprisingly quick return on investment. And you’ll be profiting ethically – you’ll be one of the angels leading the clean-up, rather than a pawn of the world’s polluting fossil fuels industry.

But here’s the issue: America isn’t acting quickly enough. We’re lagging behind in the race to adopt this critically important technology. Europe is way ahead of us. We have to catch up – and fast…

What does America’s anaerobic digestion sector look like?

The USA currently has more than 2,200 sites producing biogas:

  • 250 anaerobic digesters on farms
  • 1,269 water resource recovery facilities using an anaerobic digester (860 currently use the biogas they produce)
  • 66 standalone systems that digest food waste
  • 652 landfill gas projects.

Europe meanwhile has more than 10,000 digesters. And some communities there enjoy clean, fossil-free fuel as a result.

So the USA offers huge potential for the development of environmentally friendly and lucrative AD projects. Key states include Michigan, Idaho, Utah, the Carolinas, Oklahoma, Arkansas and Pennsylvania.

What do I need for my anaerobic digestion project?

Every AD project is based on three critical factors:

  1. Feedstock – a ready and consistent supply of biomass to feed into the AD system. You will need to secure rock-solid commitments from local farmers. They must be able to provide a steady and uninterrupted supply of animal manure and crop residue to ensure your plant operates at optimal performance.
  1. Investment to build the plant – very large digester tanks can cost more than $1 million each (and that excludes the other elements of the system, such as pumps and pipework).
  1. A return on investment – you need a dependable market for the biogas; a swift and assured revenue stream that will take your project into profit as soon as possible.

Effectively, every AD project is a ‘three-legged stool’. If any one of the three critical elements fails, the entire project fails.

How are anaerobic digestion systems constructed? Who’s who in the process?

Think of an AD project and you tend to think first about the farmers. After all, without their vital feedstock, none of this would happen. In the US, the farms are bigger because there is more land – so it may need only one farm to ‘fuel’ an AD plant. In Europe (where farms are smaller), one AD plant may serve a cooperative.

But farmers are not usually the instigators of AD projects (merely one of their many beneficiaries). Here are the key players and the crucial roles they play:

  • Independent third party
    - coordinates and supplies the investment money for the project
    - approves the design of the anaerobic digestion plant and funds its construction
    - gets commitment from farmer(s) to provide the right amount of biomass.
  • Designer
    - appointed by the independent third party
    - designs the anaerobic digestion plant for the independent third party.
  • Engineering, procurement and construction (EPC) contractor
    - appointed by the independent third party
    - builds the anaerobic digestion plant.
  • Sub-contractors, AD system dealers
    - appointed by the EPC contractor.
  • Anaerobic digestion tank manufacturer
    - usually appointed by the sub-contractors or AD system dealers
    - quality and safety are crucial so EPC contractors and other players higher up the chain will play an important role in appointing the tank manufacturer.

How soon will I see a return on my investment?

Anaerobic digestion systems pay for themselves within just five or six years.

Given the huge size of the tanks involved, they are surprisingly quick to construct as they are supplied in modular form. Even some of the largest tanks in the world may take less than two months to assemble on-site and commission.

Who are the specialists?

Balmoral Tanks is a global leader in the provision of digester tanks for AD plants. Its projects include some of the very largest digesters for multi-tank plants.

The company has just supplied two 11,500m3 tanks – among the biggest in the world – for a major AD project in Michigan. Each digester tank should generate two megawatts of power – enough to power millions of US homes for a month.

Balmoral has decades of experience. And since 2018, the company has invested more than $27 million in its 150,000sq ft state-of-the-art design and manufacturing facilities. They represent the most technically advanced production facilities in the industry – supported by unrivalled levels of expertise and service.

For this reason, many AD project co-ordinators, investors, designers and EPC contractors choose to specify Balmoral-built tanks for their anaerobic digestion plants.

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