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A single biodigester in a commercial kitchen can reduce 1000 Tonnes of CO2e over its lifetime while saving businesses money.



This proposal outlines a pilot project to achieve co-benefits of greenhouse gas emissions reductions and municipal solid waste diversion in the hospitality and food sector in Greater Sudbury, Ontario. In particular, this scalable project would create an incentive-based program for businesses in the hospitality sector to install on-site bio-digesters, which convert solid food waste into drain-safe wastewater. Liquid food composters (LFC) are high quality, technologically advanced machines capable of diverting food waste from landfill economically and sustainably.

The hospitality and food sector is the second largest sector by generated emissions in the City of Greater Sudbury for small and medium sized enterprises (SME). Producing 3,800 tonnes of waste (mostly organic) annually, Restaurants, hotels and other food service businesses are creating over 10,000 tonnes of CO2e per year. Province wide, food and organic wastes make up approximately one-third of Ontario’s waste stream and account for a significant portion of Greenhouse Gas Emissions (GHG), mostly deriving from landfill off-gassing.  A pilot program that makes this kind of technology accessible could also improve the operational efficiencies and sustainable profits for those companies that want to excel in the green economy. The proponent and coordinator of the pilot project is Green Economy North, a business-focused program that helps small and medium sized enterprises curb their GHG emissions and increase profits.



Bio-digesters are a key innovation for restaurants, hotels and other business where enormous amounts of food waste is produced. This technology provides a variety of desirable improvements to a commercial kitchen, while consistently reducing emissions.

These businesses are burdened with many issues surrounding their organic waste. These include:

  • Weekly costs associated with disposal
  • Additional costs for overweight bins
  • Impractical large/heavy bins
  • Waste bin odours
  • Pests from trash bins
  • Handling of bins
  • Unsightly appearance of bins

With an aerobic bio-digester, these can all be amended while disposing of their organic waste sustainably. Bio-digesters dispose of waste food in a clean and sanitary manner. They reduce the mess, inconvenience, cost, carbon footprint, and extra labour of discarding waste food. And best of all, have short paybacks period.

Preventing greenhouse gas emissions from landfill must be a priority as Ontario moves to meet its legislated GHG emissions targets. Significant amounts of GHG emissions come from food waste. 90% of which is from landfill emissions.4 Decomposing organic waste generates methane, which has a global warming potential 23 times that of carbon dioxide.4 Data from the Strategy for a Waste-Free Ontario report suggests increasing Ontario’s organic waste diversion by 10% would avoid an additional 275,000 tonnes of greenhouse gas emissions.4

Beyond this, the province is recognizing the need to reduce organic waste to landfill. The Ontario Climate Change Action Plan predicts the eventual ban of food and organic waste from ending up in disposal sites. This provincial ban is expected to be phased-in by 2022, though some uncertainty exists with the recent election of a new government. Assisting businesses in establishing a sustainable waste diversion system is highly beneficial for them.

The five businesses participating in this program will be provided a membership with Green Economy North (GEN). GEN is a non-profit program that provides support for businesses and organizations in Greater Sudbury to maximize the benefits of becoming environmentally sustainable. GEN is a member-based program that has repeatedly demonstrated its ability to reduce GHG emissions from Small and Medium sized Enterprises.

Beyond the monetary savings, members of the GEN program reap many other benefits and value, such as:

  • Direct Consultation and Support
  • Education Support
  • Carbon Risk Assessment, Inventory and Reporting
  • Action Plan Development
  • Resource Guides
  • Project Planning and Support with Government Grants
  • Sustainability Reporting
  • Recognition Events and Networking
  • 3rd Party Validation of Green Brand

The value proposition for businesses involved is profound. From past memberships, GEN has been able to consistently decrease businesses CO2e by more than 20%, which equates to significant monetary savings. Beyond this, the pride that comes by helping to build a more sustainable Ontario and being part of a movement that makes this sector environmentally friendly.


What actions do you propose?

We propose a four-step process in order to actualize this project.

1-Establish an Incentivized Leasing Program

By establishing a 36-month incentivized leasing program, eligible businesses in the hospitality and food sector will have the opportunity to lease 1 of 5 bio-digester units.

A bio-digester is a fully enclosed machine that disposes of most food matter within 24 hours. After thorough discussion with a Power Knot associate, it was determined that the most appropriate model for our purposes is the LFC-50 Bio-Digester, as it meets the needs of most businesses in this sector, does not require much room and is cost-effective. This model of bio-digester is a liquid food composter (LFC), meaning it turns solid food waste into drain safe wastewater. It is a high quality, technologically advanced machine capable of diverting food waste from landfill economically and sustainably. This bio-digester is all stainless steel and can digest 50-90 kg (110-200 lbs.) of food waste per day. It has a useful life of 15-25 years. The terms of the incentivized leasing program are as follows:

Brief conditions of the lease-to-own agreement are:

1. The monthly leasing fee includes:

• Shipping

• Installation, which involves connecting to the utilities provided by you

• Commissioning

• Training your staff on site for a half day

• Full service every six months

• Replenishment of consumable items

2. At the end of the 3-year lease, you may return the LFC biodigester to reThink Green to be used in another business or keep it at no charge. There is no additional cost for keeping the biodigester.

3. You are responsible for ensuring that water and AC power connections are within three feet of the right side of the LFC biodigester and a drain is within 10 feet of the left side of the LFC biodigester. Power Knot arranges connection of the LFC biodigester to these services.

This incentivized leasing program will involve purchasing 5 LFC-50 Bio-Digesters to be rented out to 5 chosen businesses in the Hospitality and food sector. The chosen businesses will pay a monthly leasing fee for 3 years. At the end of the 3 years, the businesses will be able to keep the biodigesters at no additional cost. A significant benefit, as this technology provides other immense benefits, getting it at a reduced cost is a huge bonus.

Furthermore, this incentivized leasing program will alleviate any burdens associated with maintaining the equipment as well as replenishing consumables, as these services will be provided within the leasing cost. Considering businesses tend to be slow in adopting innovative solutions and resist change, this will ensure implementation is as easy on the participating businesses. Another huge bonus!

Participating businesses will only have to cover the electrical and water costs, as the monthly leasing fee will provide the consumable items. Since the benefits of a biodigester are so immense, it is expected that participating businesses will pay for at least 50% of the total cost through the monthly leasing fee.

2- Choose 5 Businesses in the Hospitality and Food Sector

In order to maximize the impact of this project, it is important to have established criteria to determine the most suitable businesses. These businesses will firstly be able to maximize the use of the biodigester, as the more waste that is diverted, the bigger the GHG reductions. This will be based on their daily meals served. These businesses will also have a forward thinking framework engraved in their decision-making and culture, considering the innovation of these bio-digesters, having an open-minded team is essential. Businesses are responsible for ensuring that water and AC power connections are within three feet of the right side of the LFC biodigester and a drain is within 10 feet of the left side of the LFC biodigester. Power Knot arranges connection of the LFC biodigester to these services. Lastly, they will join the Green Economy North program in order to further curb their GHG emissions in other areas of their operations!

3- Chosen Businesses receive Green Economy North Program Services

As the eligibility requirements of this incentive program require that participating businesses become members of GEN, they will be on-boarded. This on boarding shares the tools available to them and begins to identify their immediate sustainability goals. Followed by the on boarding, data (electricity usage, heating waste, water, natural gas) will be gathered about their sustainability performance and a detailed action plan will be developed to realize improvements. Members will set their public reduction targets and receive community wide recognition for their sustainability achievements. GEN will follow their progress and actively assist with their continued sustainability efforts.

4- Develop a Sustainable Food Services Recognition Package

In order to enact a movement in the Hospitality and food Sector, brand recognition including a specialized window decal will be created to advertise their commitment to sustainability.

Who will take these actions?

GEN is a program of reThink Green powered by Green Economy Canada. It provides support for businesses and organizations in Greater Sudbury to maximize the benefits of becoming environmentally sustainable. Green Economy North members have access to a wide variety of support, from technical workshops to one-on-one coaching. Achievements are celebrated by the community through media coverage, special publications, and events. Green Economy North is part of a larger network, which operates in eight communities across Ontario and works with over 200 businesses. Together we are demonstrating that a more sustainable economy is possible. With a staff dedicated to environmentalism, rethink Green is aptly suited to manage this project. reThink Green will be charged with coordinating the project, sourcing materials, scheduling biyearly servicing and replenishment of consumable items and management of funds.

5 businesses need to be identified and processed in order to actualize a project such as this. The renters must be in the Hospitality and food sector and must meet the requirements set out by the project guidelines. Thankfully, due to the attractiveness of the incentivized leasing program, finding suitable participants is not a concern. The participants are responsible for ensuring that water and AC power connections are available. All the necessary components to ensure the success of this project are undertaken by reThink Green.

Where will these actions be taken?

These actions will be taken in the City Greater of Sudbury.


What are the proposal’s projected costs?

A cost analysis was conducted for both purchasing the biodigester from PowerKnot. It was determined that purchasing the units was more cost effective than renting. The calculations are shown below:

Cost Analysis to Purchase Biodigester from Power Knot

The total cost to purchase a LFC-50 Biodigester is as follows:

Capital CostUSD+ShippingUSD=$17,357 USD+$296.30 USD 

=$17,653.30 USD

Converted into CAD using an exchange rate of (1 USD = 1.31 CAD):

1.31 CADUSD × $17,653.30 USD=$23,125.82 CAD


LFC-50 Biodigester Operation Costs

The LFC-50 Biodigester has a few operating costs which are derived from the following:

  • Cost of electricity
  • Cost of water
  • Cost of Powerchips
  • Cost of Powerenzyme

The following cost analysis shows the average operating cost for a 60-month period:


Cost of electricity per kWh $0.09

Typical energy used per day 4.1kWh

Cost of electricity per day $0.38


Cost of water per 1000 litre (1 m³) $3.80

Typical water used per day 150 litres

Cost of water per day $0.57


Cost of water and electricity, per day $0.95

Cost of water and electricity, per month $28.92


Cost of Powerchips™ for this LFC biodigester $530.00

Life of Powerchips 36 months

Monthly cost of Powerchips $14.72


Cost of Powerzyme™ for this LFC biodigester $160.00

Life of Powerzyme 12 months

Monthly cost of Powerzyme $13.33


Cost of Powerchips for first 60 months $353.33

Cost of Powerzyme for first 60 months $640.00

Total cost of consumable items for first 60 months $993.33


Cost of water and electricity for 60 months $1,735.03

Total operating costs (utilities + consumables) for first 60 months $2,728.36

Total monthly operating costs averaged over first 60 months $45.47


The total monthly operating cost averaged over 60 months is just under $46.


Monthly Leasing Fee

The total cost for one biodigester is $23.126. The total operating cost for one biodigester in a 36-month period is as follows:

$45.47months × 36 months=$1,636.92 CAD

Participating businesses will only have to cover the electrical and water costs, as the monthly leasing fee will provide the consumable items. The cost for the consumable items for 36 months, using the data provided above, is as follows:

Monthly Cost of Powerchips+Monthly Cost of Powerzyme

$530.0036 months+$160.0012 mont??s =$28.05/month

The total cost not including utility expenses for a 36-month period is:

Total Cost=Cost of Consumable Items+Capital Cost+Safety+Installation

= $28.05month ×36month+$23,125.82+$500+($250) 


The total cost necessary to fund one biodigester is $24,886. It is expected that the leasing cost paid by participants will cover 50% of this cost over a 36-month period. Therefore the following calculation determines the monthly fee to be payed by participating businesses:

Monthly Rental Expense=$24.885.6236 months × 50%=$345.63 

The Proposals Projected Cost

The cost of this proposal is the total cost of a biodigester, multiplied by the number of purchased biodigesters .The proposals projected cost is:

Proposal Projected Cost=$24,885.62 digester × 5 digesters=$124,428 



As climate change awareness and the negative impacts from it become more prevalent, societal demands on businesses to be environmentally friendly are becoming more common. Additionally, the benefits of a bio-digester and a membership with GEN are significant. It is expected that the pilot project will demonstrate results that are attractive to other businesses (e.g., cost savings), encouraging them to adopt similar technologies.

As it stands, bio-digesters are not commonly used and few early adopters have taken the leap. By implementing this project, bio-digesters and the GEN membership will become a staple in forward thinking businesses. Beyond this, Ontario’s Climate Change Action Plan has the intent of banning food waste to landfill and incorporate standardized training for owners and operators on aerobic digestion. For this reason, this project will be a major stepping-stone in improving Ontario’s food and organic waste framework, as businesses will recognize its ease.

Using a specialized window decal to advertise the participating businesses commitment to sustainability will be used. This is intended to bring awareness and recognition to the participants as well as setting a new standard of sustainability within the sector. By doing so, change will be enacted more quickly due to increased awareness.


The realization that there is a more convenient way of disposing of organic waste, all while reducing the carbon footprint and saving money is a strong value proposition. It is evident that once bio-digesters find their way in the Greater Sudbury community, a new trend of diverting waste in a sustainable matter will manifest. At some point in the change process, achieving momentum through tangible results will start to generate its own energy and fuel the process. This solution to disposing of food waste is significant and has the potential to reach 335 businesses in Greater Sudbury and thousands more across Ontario. Considering the simplicity of the solution, its well-defined benefits and ease of implementation, it should be sufficient to convincingly address businesses.




Using data from the research article “Evaluation of landfill gas emissions from municipal solid waste landfills for the life-cycle analysis of waste-to-energy pathways”, the GHG emissions reductions were determined and are as follows:

It was concluded that GHG emissions from landfilled food waste could emit an average of 2713 kg of CO2e per dry tonne.

These GHG reduction calculations do not account for the decrease in trucks hauling waste. Considering a LFC 50 bio-digester can digest 50 kg a day, it has the following GHG reduction potential:

Average emissions per day

2713 kgCO2e/dry tonne× 50kg/day × 1tonne/1000 kg=135.65 kg CO2e/day 

Average emissions per year:

135.65 kgCO2e/day × 365days/year × 1tonne/1000 kg=49.5 tCO2e/year

GHG Reduction from Sudbury Biodigesters Project

 49.5tCO2e/year×5 BioDigesters=248 tCO2e/year

Considering the life of one biodigester is 20 years, GHG reduction for the entire life of this proposal:

GHG Reduction from Sudbury Biodigester Project=4,960 tCO2e

What are other key benefits?

-Helping SMEs identify the largest opportunities for GHG reductions impact and identify a focused path forward is our mandate. Our framework has seen success through its attractive value proposition and continues to grow.

-The LFC-50 Biodigesters software. All configurations, indication, reports and statistics are available trough the touch screen and can be sent by email. This allows for analysis of bio-digester use, helping in reducing food waste and making more educated business decisions. It also tracks the amount of CO2e curbed from landfill as a result of its operation.

The highly concentrated organic load produced makes its way to Sudbury’s Biosolids Management Facility. This facility is an environmentally responsible and sustainable plant that turns organic residuals into an agricultural and beneficial soil amendment, used primarily in the agricultural sector and for land reclamation projects. The sale of the biosolids end product generates revenue for the municipality.

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