FAQs
1. What volume of waste needs to occur for an anaerobic digestion project to become viable?
The volume of waste or by-products required for an on-site anaerobic digestion plant to be feasible depends on a number of factors. These include the energy potential of feedstock, current disposal route and costs, energy demand and current prices. Minimum volumes will be in the region of 10,000t pa for solid waste or 50,000m3 pa for high strength liquid waste.
Smaller sites can sustain such an approach if by-products which are currently sold (e.g. for animal feeds) may be more valuable if converted to energy or if feedstock is imported by other nearby businesses. At the outset of each project, InSource Energy conducts a free, confidential in-depth analysis of the feedstock profile and volumes to ensure the project’s economic feasibility.
2. What type of material can be used as feedstock?
The feedstock profile could range from high COD effluent, unwanted waste by-products, to unavoidable waste from run-ons etc. Packaged food waste, including meat products, is all viable feedstock.
3. How large does my site need to be to host the necessary anaerobic digestion facilities?
An anaerobic digestion plant can be built on as little as one acre of land. It is also possible to add the AD facilities to your existing effluent or waste treatment facilities. Alternatively, it may be possible to develop a shared AD facility with other nearby smaller sites too.
4. How long does it take to install and commission an anaerobic digestion plant?
Installation and commissioning an anaerobic digestion plant usually takes about six to 12 months, including the connection to your existing plant. The first step in a successful anaerobic digestion project is to conduct a feasibility study, which typically takes about one month. This paves the way for the design and development of the most appropriate technology solution, after which the necessary planning consents need to be obtained. The project development process requires significant technical, risk management and sector expertise, and can typically take 6-18 months.
5. Can I build my own anaerobic digestion facility?
It is possible to obtain the necessary plant direct from manufacturers. However, it is important to be aware of the boundaries of responsibilities to understand the cost and risk implications of whom is responsible for the technical solution design, procurement of necessary machinery, connections between the existing and new plant, management of the planning process, installation, commissioning and operating the plant, with the necessary recruitment, staff management and payroll overheads. InSource Energy are happy to discuss Joint Ventures with clients who wish to have an ownership stake in the project and also offers a “build, own, operate, transfer” model that also circumvents these risks and the need for capital.
6. How much capital is required to develop and commission an anaerobic digestion plant?
InSource Energy offers two business models: “build, own and operate” where there is no capital requirement of the host site as InSource Energy develops, owns and operates the plant and secondly, “build, own, operate and transfer” where the client can invest in the facility at a predetermined point. Under both these models, the client has no initial investment and instead focuses on running the core business, paying only waste gate and energy used at fixed, below-market rates.
7. How long are the energy prices fixed at below-market rates?
For the life of the plant InSource Energy offers discounted waste disposal and energy prices. The contract term is typically 15 years and with the inflationary index predetermined and agreed at the start of the project.
8. What happens if the waste volume or composition changes?
InSource Energy conducts a free, in-depth economic feasibility study for each project so that all parties have a clear understanding of the waste volume and profile from the outset. If the waste volumes increase, for example through increased production, then the plant usually can be scaled to accommodate this. A minimum feedstock guarantee will be agreed before contract sign off.
9. By how much will the effluent COD sent to sewer reduce?
An InSource Energy high rate anaerobic digestion plant facility could see as much as a 95% reduction in COD load to sewer. This can remove a barrier to growth for many businesses that are constrained by the volume of effluent going to sewer.
10. Can an anaerobic digestion facility cope with the removal of plastic packaging?
Yes, as in the case of the InSource Energy Rogerstone plant: The £5m facility, designed, financed and operated by InSource Energy, is converting RF Brookes’ food waste into energy to help power the factory, which is the leading supplier of ready meals to Marks & Spencer. Our technical design uniquely incorporated both pasteurisation for treating animal by-product and depackaging for handing packaged food waste and contaminated plastics.
