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The market of new waste-to-energy and waste conversion technologies is rapidly evolving with new facilities being announced and operating data on bench scale and pilot facilities being received to fill in the current gaps on plant operating history. By asking the right questions, decision-makers can take steps to ensure that what is being promised is what they will receive.
By Marc J. Rogoff, Ph.D.

Companies representing innovative technologies to process and dispose of solid waste in an environmentally conscious and sustainable manner have been actively promoting their systems to governmental agencies worldwide. As a result, development offers for systems employing technologies or processes that divert waste from disposal, such as anaerobic digestion, gasification, plasma arc, and pyrolysis are becoming commonplace. Table 1 provides some basic, commonplace definitions of these technologies seen in proposals and presentations. Figure 1 shows the classification of these technologies.

Because the systems are new and there are few successfully operating commercial-scale plants, there is a certain amount of risk and uncertainty experienced by officials who must weigh the merits of the technology, the resources and experience of these companies, and how it would benefit the public.

‘Over the past 30 years, I have provided critical advice to public decision makers as they evaluate waste-to-energy and waste conversion technologies options. This article provides a summary of the 10 definitive questions and background that officials can use in their due diligence assessment of these recent technologies. Over the past 30 years, many technology providers have come and gone, while others have entered the marketplace. Decision makers have the challenging task of assessing the difference between a solicitation that has a high degree of project viability versus one that is too good to be true. What is the truthful answer?

A Hypothetical Situation
At a hypothetical government council meeting, a presentation is made to significantly change the way municipal solid waste (MSW) is managed by the local government. In our hypothetical story, the presenter is the president of a modern technology company, and he describes his company鈥檚 process of 鈥渆liminating waste by thermally converting it to useful products and energy.鈥� Their proprietary, revolutionary technology would take unprocessed or minimally processed household waste and turn it into green energy and useful products in a pollution-neutral, enclosed facility that would employ up to 200 local people in 鈥済ood, well-paid jobs.鈥� The company states it would not ask for tax abatements and would pay local property taxes on its plants and improvements. Further, it would provide its own financing to construct the facility. The president only asks that the Council provide about 200 acres for construction of the plant nor a nominal lease payment and endorsement of the final financing package to take advantage of federal tax savings, and a contractual agreement to provide him all your waste for 20 years.

Under these circumstances and with limited information provided during the presentation, what should the local decision makers to do? The deal presented is very intriguing; it is hard to say no since financing the existing solid waste management system demands a lot of capital, and this offer has negligible risk, a huge upside potential with regard to jobs, and positive media exposure. In addition, it truly eliminates the need to own and operate a landfill. The scenario briefly outlined above is taking place in local governments across the U.S. and many international venues as well. Hard pressed with paying for the increasing cost of landfill disposal and more restrictive environmental regulation, many agencies are looking to new and innovative, but often commercially unproven technologies. These technologies promise to turn municipal solid waste into an asset that produces energy, usually either electric power, vehicle fuels, and/or renewable methane, and generate useful by-products that can be turned into consumer products, building materials, or as soil conditioners for agriculture.
How should political decision-makers decide the best way to go forward with such a proposal? Due diligence should include evaluation of the following critical issues. Normally, much of this information can be gathered and assessed in a pre-feasibility analysis undertaken by an independent, third-party reviewer. Here are the top 10 issues that public officials should be focused upon.

Question #1: Does the Technology Work?
The technical veracity of the technology proposed by the vendor is the most critical issue that must be resolved at the outset. Since the risks associated with waste-to-energy (WTE) technology can be substantial, it is critical that the following considerations be used to assess the relative risk of a particular technology:

鈥� Actual Plant Operating Experience鈥擲ome technologies may only have been evaluated at a pilot scale or even laboratory scale, while others have only been operated using carefully screened feedstock materials other than MSW. Many of these experimental units have not been run continuously over a significant period to gauge reliability, and the ability of final outputs to be sold in the local marketplace has not been established. MSW is a non-homogenous, ever-changing mix and this complicates the design of basic conversion processes compared to treating; for example, a single, consistent material such as sawmill residue.

鈥� Scale-Up Issues鈥擯ast history suggests that some companies without considerable experience on their own prototype or pilot plant try to jump into construction and operation at full-scale. In this case, there is an elevated risk of significant startup issues that could significantly delay or prevent operation at the expected throughput capacity, or even result in total failure. To manage/reduce the scale-up issues and risks associated with custom-built plants, some vendors are producing smaller, off the shelf 鈥渕odules鈥� that can be combined to meet the client鈥檚 throughput requirements. This strategy has some positive advantages, like mechanical consistency and process redundancy, however, it increases the complexity of the plant and will require more maintenance. There is no shortcut to the scale-up issue with a modern technology, as a comparison, the high reliability of conventional WTE plants have evolved through operating commercial plants over a span of more than three decades.

鈥� Need for Pre-Processing of the Waste Stream鈥� Many of the new waste processing technologies are borrowed from the chemical industry where they run quite well with a single chemical or related family of chemicals. MSW is an heterogenous mix of material types and sizes, including putrescibles, organics, plastics, glass and ceramics, and metals, including heavy metals that are that are not necessarily desirable in the treatment process or in the final products that are being marketed Careful inquiry should be made to determine what level of pre-processing is required to remove contaminants, then the extra cost for processing must be included in the financial package. Typically, a material recovery facility (MRF) is used for this purpose. Depending on their complexity and capacity, MRFs can cost multi-millions of dollars and incur high maintenance costs.

鈥� Mechanical Reliability鈥擳he technology selected must be capable of processing MSW in a reliable manner without frequent mechanical downtimes resulting in diversion of such waste to landfills. Early years of plant operations may require constant adjustments or modifications to systems to improve operating performance. The time limit for adjusting the initial operation is referred to as the 鈥渟hakedown鈥� period and often at the end of the shakedown period the actual throughput can be significantly less than what was designed, resulting in additional processing cost or the need to divert some materials for disposal.

Question #2: What Is the Strength of the Company?
Once the question of plant technology is addressed, it is important to learn the strength of the company proposing the technology of your project. Does this company have the basic business strength to secure the required capital for the project and to be able to work through and appropriately fund promptly the normal plant operational hiccups during the first few years of plant shakedown? Further, does the company have the intellectual property and patent rights for the technology? Are these rights reflected in the projected capital and operating costs for the project? All these questions and more need to be answered so your agency can be assured that the company proposing the plant has the resources to meet the operating challenges.

Again, this waste conversion market is rapidly evolving with inexperienced players entering the marketplace. Many of these are exceptionally large corporations with strong balance sheets able to either provide parent guarantees on plant performance or have become significant investors in these technologies.

Question #3: Does This Project Fit in with the Current Solid Waste Program?
Solid waste management has evolved over the past several decades to one that emphasizes integrated solutions to management of solid waste including waste reduction, waste recycling, collection and transport, and waste disposal. As a result, there are often multiple contracts, vendors, and facilities that manage a portion of the waste stream. Consequently, it is important to assess realistically how a new alternative technology may fit in the community鈥檚 long-term, solid waste plan. It is critical to assess how current waste collection, recycling, and processing programs mesh with the proposed facility. Will the waste collection contract or franchise agreement need to be changed if the recent technology is adopted? Does the new facility mean that an existing vendor will leave without a contract? Is a transfer station needed if the proposed facility location is more distant that the current disposal location? Lastly, do the changes require a modification of the existing plan and a later regulatory submittal to a state agency?

Question #4: Can You Provide Waste Supply for the Plant?
Innovative technologies are capital intensive and developers will require a consistent, long-term revenue stream before committing to a develop a facility. Decision makers must determine if they have the legal authority to direct waste generated in the community to the proposed facility. Will agreements need to be secured with other haulers? Is a flow-control ordinance required? Further, does the community have enough waste to support the projected needs for the plant over the entire life of the contract? Will waste have to be imported from outside the community? These issues can be politically charged questions that could take some time to resolve, especially if flow-control rules need to be enacted.

Question #5: What Are the Siting Needs For the Facility?
Any solid waste processing facility will require property and infrastructure beyond the footprint of the main building to receive and queue incoming trucks, connect to public roads and utilities, and temporarily store feedstock and end products. Is there an appropriated sized parcel of land available that is properly zoned for the proposed facility? Further, what other community facilities would be needed such as an electrical transmission tie-line, wastewater connection, water supply, paving, etc., and who would pay for these costs (which can be large)? The feasibility assessment of the project must consider a clear understanding of what is provided by each party and what costs are involved. Also, as with most solid waste projects, there could be an adverse reaction from neighbors in the proposed facility. You will have to be able to convince the neighbors that this will not adversely affect their health, safety, or property values.

Question #6: What Kind of Permits Will Be Needed?
While innovative waste conversion technologies tout the potential benefits for waste diversion from landfills, the ability to generate renewable power, and reduce your carbon footprint as compared to traditional waste management methods, experience with similar waste conversion technologies suggests that most facilities of this type will require a significant amount of environmental permitting. What are the air emissions generated from the facility? Is there a wastewater stream that is generated that must be treated? What are the residues that are left over after treatment? Depending on the process, specific permit approvals may be required from state regulatory agencies for solid waste, air, and water. Lastly, there may also be issues with land use permits or conditional use plants if the technology is not clearly defined in local or State regulations.

Question #7: Are Markets Available for the Products And Energy?
One of the main incentives for pursuing innovative technologies is the generation of useful energy and products from waste. Energy examples include renewable natural gas, syngas, liquid fuels, and electricity. Product examples include rock-like slag, heavy oil, ash, sulfur compounds, fertilizer substitutes, and metal slag. The composition of the by-products depends on the composition of the waste put into the conversion system and the specific processing technology and operating conditions. Because there are many variables that impact the quality and quantity of the products produced, relying on data provided by the vendors may not be sufficient. It is important to note that the financial viability of waste processing technologies is often dependent on the revenue that is made by selling the energy and products produced. Therefore, a feasibility analysis should include the existence and stability of an end market for the products produced, whether the prices paid in the market are stable or volatile, and the risk of price variability on the financial stability of the facility. For example, a waste processing facility may generate a product that could substitute for commercial fertilizers, but if major farming operations are hundreds of miles away or there are already very inexpensive fertilizers dominating the market (e.g. manure from poultry operations), then what may have seemed to be an opportunity to generate revenue could easily turn into a wastewater that must be treated.

Question #8: What Are the Costs?
All the answers to the preceding questions can be translated into a series of projected revenues and expenses for the project. Typically, this is conducted using traditional Pro Forma economic models, which can provide a series of 鈥渨hat if鈥� scenarios that calculate the short-term and long-term economic impacts. These models also make conducting a 鈥渟ensitivity analysis鈥� efficient and helpful to assess the effects of varying costs and/or revenues. Key to this modeling work is obtaining exact and realistic capital and operating costs for the proposed project. As mentioned at the outset, these data are increasingly available from pilot facilities. It is important to review the assumptions and ensure that they accurately reflect the roles and responsibilities of the local government with respect to their project.

Some plant developers will offer the community a disposal fee, the 鈥渢ipping fee,鈥� at the plant comparable to the government鈥檚 current disposal fee. However, that fee may be based on a scenario where the new plant operates at 90 percent or greater uptime, there are no major modifications needed within the first year or two of operation, waste is imported from other regions to boost production, and the price the developer gets for the energy production does not fluctuate. Some of these factors may be overly optimistic. For example, a plant with recent technology rarely uses at 90 percent uptime, it is usually lower; costly modifications also can be necessary after start-up reveals problems in the design. The price of energy can go down. Residents of the community may object to the importation of another region鈥檚 waste. These changes may force the developer to renegotiate for a higher disposal fee. The fact is that because the plant is new and may be untested at a commercial operating ability, the genuine cost of disposal cannot be predicted accurately and may not actually be known for a few years after start-up.

Question #9: Will There Be Financing Risks?
There are many project financing mechanisms available for public-private projects including options such as government loan guarantees and state credit enhancements that can to improve the financing of innovative projects. The primary question for local decision makers is if public financing or a public guarantee of financing is being requested from the developer. It is important that as these 鈥渄eals鈥� mature that the community understand what financial risks, if any, they manage. Will the taxpayers be on the hook for the loan should the project not work out? A well-seasoned financial advisor is essential to help give the community the advice needed to understand and negotiate these financial risks.

Question #10: What Happens If All Else Fails?
A lot is at stake. You are about to potentially give away one, if not the most valuable revenue sources your community owns鈥攊ts waste. In addition, you are potentially compromising the integrity of your system by giving away control of your waste鈥檚 final disposal system. If this recent technology should not work and the plant is shutdown temporarily or even permanently, can you re-open your old landfill? Where will the waste go if the plant is shut down? Who will manage that and the extra costs?

Some Final Thoughts
A waste-to-energy or waste conversion facility is the single most complex public works project usually considered by a community. Not unlike the traditional mass burn and RDF facilities, the feasibility assessment of such projects should be undertaken in a methodical process of finding the answers to key questions upfront. This will assure the public and decision-makers that all relevant issues have been explored and a resolution reached before significant private and public resources are spent on such projects. Even if you are willing to accept the risk of an emerging technology, there is a vast difference between taking a well-thought out, reasonable risk versus simply chasing a press release and then hoping for the best. Stick with proven technologies that you can see in operation. Talk with your peers in communities that have the technology and get the real story on what it costs to build and run.

The market of new WTE and waste conversion technologies is rapidly evolving with new facilities being announced and operating data on bench scale and pilot facilities being received to fill in the current gaps on plant operating history. This is beginning to make the job of assessing the claims for these technologies more efficient and correct. These assessments, conducted by an independent third party, help decision makers by providing a clear, concise, and un-biased tool that they can use in working through the decision-making process. The next few years will see many success stories involving these recent technologies. By asking the right questions, decision-makers can take steps to ensure that what is being promised is what they will receive. And that is a big step to becoming another one of this industry鈥檚 success stories. | WA

Marc Rogoff, Ph.D., is a Senior Consultant with Geosyntec Consultants. He has experience in the development of waste-to-energy and waste conversion projects from the initial feasibility to commercial operations monitoring. He has conducted bond feasibility studies totaling $1.2 billion in project financing, operations assessments, and provided recommendation on key procurement issues. Dr. Rogoff has conducted technical feasibility studies on more than 50 waste-to-energy facilities worldwide, including 35 assessments of waste conversion projects evaluating their technical veracity. Marc can be reached at (813) 810-5547, e-mail [email protected] or via LinkedIn at .

References
Municipality of Anchorage, Solid Waste Services, White Paper Report: Development of a Waste-to-Energy Project for the Municipality of Anchorage, Alaska, September 2021. Prepared by Geosyntec Consultants.
Rogoff, Marc J. and Francois Screve, Waste-to-Energy Technologies and Project Implementation, Elsevier, Third Edition, 2019.
Rogoff, Marc J. and Bruce Clark, Staying Informed of Solid Waste Disposal Options, Public Management, September 2012.