House of Lords - Waste or resource? Stimulating a bioeconomy

Waste or resource? Stimulating a bioeconomy - Science and Technology Committee Contents

Chapter 2: The Opportunity

A Bioeconomy

13. A bioeconomy can make use of a range of feedstocks and use different processes to convert these feedstocks into a wide variety of different products. Examples of the wide range of feedstocks, products and processes involved in a bioeconomy are provided in Figure 2.

FIGURE 2

Feedstocks, processes and products in a bioeconomy

This sets out what is put into the bioeconomy (the feedstock) what is done with it (the process) and what comes out at the other end (the product). The diagram divides feedstocks into two major catagories: 'first generation,' and 'second and third generation.' This is because the science was initially developed using 'first generation' feedstocks, containing easy to access carbon. These feedstocks were predominantly food crops, such as oilseeds or sugar beet. 'Second and third generation' feedstocks contain carbon which is more difficult to access or make use of. Such feedstocks include dedicated non-food crops (such as willow or algae), co-products (or by-products - which are usually formed at any stage of processing and are not explicitly identified in the figure) and waste. Only co-products, by-products and waste are included within the scope of this inquiry. Although agricultural and forestry residues are shown as a waste within the figure, it is important to note that in many cases they have an existing use and should therefore be classified as a co-product or by-product. Liquid waste comprises organics in untreated water, particularly the organic fraction of sewage sludge in municipal waste water treatment and other waste streams such as those from the food processing industry. Three main types of processes are illustrated in the diagram: thermochemical, chemical and bioprocessing. Bioprocessing can produce materials through enzymatic processes or aerobic conversion or it can produce biogas through anaerobic digestion. Products are illustrated in the figure in order of increasing value, with the lowest value at the bottom of the column. Chemicals are at the top end of the value chain. Some processes will result in the direct production of the desired chemical product. In other cases there is an intermediate step, where a platform chemical is produced, which is then converted into the desired product. Chemical products include fine chemicals and pharmaceuticals, speciality chemicals, polymers and commodity chemicals. This figure was provided by A.D. Little.

FEEDSTOCKS

14. Waste has the potential to provide an important feedstock for the bioeconomy. We heard that:

"Waste biorefining has the potential to completely eliminate the competition for land that is inherent in the use of most other feedstocks, such as food crops. This may result in waste becoming the most sustainable feedstock of all."[24]

15. Whilst this may be an optimistic view, waste can certainly make an important contribution to fuelling a bioeconomy, and can therefore be transformed from a problem into a resource. As set out in Figure 2 above, carbon-containing wastes come in different forms and from different sources. This includes municipal solid waste, which is the 'black bin bag waste,' from households and similar sources, which is collected by municipal authorities. It also includes a proportion of commercial and industrial waste and construction and demolition waste, which is collected separately by specialist firms.

16. There are mixed waste streams and also segregated wastes, such as food waste and green waste from parks and gardens. Food supply chain wastes such as potato peelings, pea pods or orange peel provide particularly good sources of feedstock for a bioeconomy as they have a consistent composition.[25] The generation of wastes such as these are unavoidable, and yet we were told that they can provide a rich source of valuable chemicals. Agricultural residues, forestry residues and liquid wastes such as sewage sludge can also provide feedstocks for a bioeconomy. Finally, gases like carbon monoxide, carbon dioxide and hydrogen, which would usually be emitted to the atmosphere or burnt, can be captured and used as a feedstock for the bioeconomy. These gases are emitted from industrial processes, such as from steel mills, oil refineries or natural gas extraction.[26] Large amounts of methane are produced from managed landfill sites.[27] Paragraphs 28 to 41 provide further information on the types and quantities of waste available.

PROCESSES

17. A range of processes can be used to transform wastes into useful products. Rather than using fossil fuels as a source of carbon, waste can be used instead. The carbon in waste, however, is present in a less easily accessible form. It is usually necessary to begin by breaking the carbon in solid and liquid wastes down into simpler molecules. This can be done using high temperature, thermochemical processes, using chemical processes, or using biological processes (Figure 2 above). Although many different processes have been developed, it can be challenging to ensure that the feedstock-process-product combination represents an economically and environmentally viable proposition.

18. Thermochemical processes, such as pyrolysis and gasification, involve heating municipal waste or biomass residues to high temperatures to produce 'syngas,' a mixture of methane, hydrogen and carbon monoxide. This gas can be burnt to generate energy, cleaned up and injected into the gas grid, or used as a feedstock for further reactions to generate fuels or other chemicals.[28]

19. As an alternative to high temperatures, catalysts or enzymes can be used in reactions to transform the carbon in waste into sugars and then into useful chemicals. Biological processes, which make use of the ability of microbes to digest complex molecules and create chemicals, can also be used. Biological processes include fermentation and anaerobic digestion. In some cases the microbes used in these processes can be found in nature. In other cases, synthetic biology approaches can be used to adapt microbes to undertake a particular function. We heard that there was considerable potential for synthetic biology. By specifically altering the DNA of microbes, it is becoming possible to make use of an increasingly wide range of feedstocks or substrates and to produce valuable chemicals:

"With the advent of synthetic biology, because the costs now of building genetic material—building DNA—are now much cheaper than they were, we have a great repertoire of potential genes that we can put into the organism chassis to produce these products. For me the trick of this is the A to Z of pulling through the substrate flexibility through the organism chassis and also developing the pathway that will produce the high-value product with the minimum of other contaminant byproducts. The UK research base is superb in terms of how it drives itself."[29]

20. We were informed that microbes can be used to directly fix waste gases (Figure 3 and Box 2) and produce useful chemicals.[30] These gases can be high volume by-products of industrial processes such as steel production. Syngas produced from solid wastes, landfill gases or biogas produced by anaerobic digestion can also provide feedstocks.[31]

FIGURE 3

Gas fermenting microbes

Gas fermenting microbes, such as Clostridium autoethanogenum, can be used to transform carbon monoxide (CO) and hydrogen (H₂) into useful chemicals. As illustrated in this figure, the microbe transforms CO and H₂ gases into useful chemicals through metabolic pathways, involving the key metabolic intermediates Acetyl Coenzyme A (Acetyl-CoA), pyruvate, as well as fatty acids and terpanoids (secondary metabolites). A range of alcohols such as ethanol and isopropanol or acids such as 3-Hydroxypropionic Acid (3-HP) and succinate are produced at different points of the metabolic pathway. The figure shows the progress of this technology, using C. autoethanogenum, through different Technology Readiness Levels.[32] It is already possible to use this technology to produce ethanol at the pre-commercial, demonstration (demo) scale. Lab-scale production of isopropanol, acetone and 1-butanol is also possible. At the discovery stage, research is underway to produce chemicals such as isobutylene and isoprene. In the future, using synthetic biology, it may be possible to use C. autoethanogenum to directly produce advanced biofuels, speciality chemicals and platform chemicals from waste gases. This figure was provided by LanzaTech.

21. Several of the processes described above are often coupled together to transform waste feedstocks into useful products. Indeed, it has been suggested that there is a need to develop 'green biorefineries,' where processes are brought together, enabling flexibility in the type of feedstock used and generating multiple products in the same way as oil refineries do today (Figure 4):

"The integrated biorefinery would make full use of all the components of multiple feedstocks (particularly cellulosic and waste streams) to produce value-added multiple co-products including energy (electricity and steam) and various bio-based chemicals and plastics, along with fuel-grade ethanol or other fuels, and perhaps even other products such as paper."[33]

FIGURE 4

The integrated biorefinery concept[34]

PRODUCTS

22. The processes described above can generate a range of different products. As the Royal Society of Chemistry told us:

"Sugars, oils and other compounds in bio-waste can be converted into platform chemicals directly. These building block chemicals have a high transformation potential for conversion into new families of useful molecules such as lubricant, flavours, nutriceuticals, solvents, polymers and pharmaceuticals."[35]

23. At the most basic level, gases such as methane, produced from anaerobic digestion, can be combusted to generate heat and power and digestate can be spread to land. Alternatively, methane can be cleaned up to be injected into the gas grid. Methane can also be converted into other products. For example, Calysta Energy told us about their technology which can be used in producing biodegradable plastic from methane, and that, "in the future, we will be able to convert biogas to methanol, a basic chemical building block and also a valuable gasoline additive."[36] This type of technology has the potential to create more valuable products for the bioeconomy.

24. Biofuels for road transport or for aviation can also be produced from waste (Box 2).[37] In addition, bioethanol can be used as a building block to generate other higher value products. We heard that a range of commodity chemicals could be produced. Green Biologics told us about their technology for transforming household waste into biobutanol, which:

"… goes into the chemical market. It is a relatively high-value commodity chemical. It forms a precursor for polymers, plastics, paints, coatings in a market worth approximately $6 billion. Also it is a very good advanced biofuel."[38]

BOX 2

Case studies: sustainable aviation fuels—Virgin Atlantic and British Airways

"In October 2011 we [Virgin Atlantic] announced our partnership with LanzaTech to pioneer their ground breaking new technology, to develop the first of the next generation of low carbon fuels. Their technology uses a microbe to convert waste carbon monoxide gases from steel mills (which would otherwise be flared off direct to the atmosphere as CO₂) into ethanol. The alcohol is then converted to jet fuel through a second stage process. Initial Life Cycle Analyses suggest that the resulting biofuel will emit 60% less carbon than the fossil fuel it will replace, kerosene. Moreover, because it uses a waste-stream, it creates a biofuel that does not impact on land use or food production. We're pleased to report that LanzaTech recently secured Roundtable of Sustainable Biomaterial (RSB) approval for the plant in China that will produce our first fuel. RSB is widely agreed to be the gold standard sustainability certification scheme for biofuels. The process is also expected to improve local air quality in the vicinity of steel plants by reducing emissions of nitrogen oxide and other particulate emissions.

The technology is scalable. The first plant in China will produce enough fuel for us to uplift all of our fuel out of Shanghai as a 50:50 mix with kerosene, with plenty left over for other customers. In addition, LanzaTech estimates that its process could apply to 65% of the world's steel mills, offering the potential to provide up to 19% of the world's current jet fuel demand."[39]

"British Airways is working with a US-based technology company to construct a state-of-the-art facility that will convert around 500,000 tonnes of waste normally destined for landfill—into 50,000 tonnes of sustainable low-carbon jet fuel, 50,000 tonnes of biodiesel and 20,000 tonnes of bio-naphtha per annum. The plant itself will be powered by the waste feedstock. The work on the detailed plant design is about to commence and we expect construction to begin in early 2015 …

The Solena Greensky project intends to use residual waste that has been processed via Mechanical and Biological Treatment (MBT) from the South East of England. Solena's plasma technology is feedstock flexible and can take a wide variety of materials, including waste agricultural material, waste wood etc. However, economics favour the use of residual materials that would otherwise be destined to go to landfill or incineration …

The use of residual wastes yields very high greenhouse gas lifecycle savings and avoids the conflict with land use and food production that affects some other biofuel production methods. In addition lower costs (or even negative cost) of feedstock makes these technologies more economically viable. Many

waste-derived fuels only require minimal incentives to make them cost competitive with first generation technologies. More challenging are the barriers to investment which are as a result of policy uncertainty and investors' attitudes to investing in first-of-a-kind projects."[40]

25. We also heard about speciality chemicals. For example, Professor James Clark from the University of York told us about the extraction of flavours, fragrances and solvents from citrus peel:

"We already take out oils from citrus waste in some other countries for various applications, flavours and fragrances and so on. We can also now get solvents. Limonene, a very well-known chemical you can get from citrus waste, is now being used for cleaning printer circuit boards, displacing halogenated chemicals, so also providing a greener, safer alternative to current technology. Similarly with citrus waste, you can also get materials like pectin, which is widely used in the food industry. That is happening already and I think could happen a lot more."[41]

26. In addition, it is possible to produce entirely novel products with novel properties. Dr Philp from the OECD noted that: "the laboratory biosynthesis of 1,4-butanediol has also been described, a significant achievement as it is an entirely synthetic compound without natural precedent."[42]

27. To maximise the potential of the bioeconomy, it will be important to extract as much value from waste as possible, and ensure that higher value products, such as commodity and speciality chemicals are generated. This inquiry asked how processes, which deliver maximum value from carbon-containing waste, can be supported.

Waste as a resource

28. During this inquiry, we received a wide range of different figures relating to the amounts of waste produced, managed and disposed of. According to figures provided by the Department for Environment, Food and Rural Affairs (Defra), in 2010 the UK disposed of, or recovered, 286 million tonnes of waste.[43] Figure 5 provides information on the sources of waste, the types of waste, and the treatment of waste in the UK as classified into the broad categories required for EU reporting purposes. This includes types of waste which do not fall within the scope of this inquiry. The UK is making progress both in terms of reducing the amount of waste sent to landfill and increasing the amount recovered.[44] There is, however, clearly further room for improvement.

FIGURE 5

Sources, types and treatments of waste in the whole of the UK in 2010

Data provided by Defra.[45] The two waste arisings charts present percentage values of a total of 218 million tonnes of waste. The waste 'disposals' chart presents percentage values of a total of 286 million tonnes of waste. Arising and disposal figures are best estimates and do not reconcile as completely different data sources are used. Less than 1% of waste (316 thousand tonnes) enters energy recovery. Backfilling into excavated areas is classed as a form of recovery as the use of waste for this purpose replaces the use of other materials.

29. Not all of this waste is carbon-containing waste which could be used for the bioeconomy. Of the categories described in Figure 5, wastes of relevance to our inquiry are predominantly animal and vegetable waste, paper and a proportion of general and mixed waste. The evidence we heard suggested that between 100 million tonnes and 150 million tonnes of carbon-containing waste is generated in the UK.

"Here in the UK, on the generally-accepted figures, we have about 120 million tonnes of biomass-type material. If you include carbon material, 130 million to 150 million tonnes of carbon-based material is flowing through a system. Some of that is pure biomass, some of it is impure like cardboard, and some of it is pure carbon like plastics and so forth."[46]

30. Defra estimates that 100 million tonnes of biowaste is available for biogas production.[47] This includes agricultural residues, food and drink waste and sewage sludge. We also heard that nine million tonnes of residual waste, comprising bio-waste and plastic, remains after recyclable plastic, metal and glass has been removed from unsegregated household waste.[48] WRAP provided further information on the amounts of different types of biowaste and waste plastic generated in the UK (Figure 6).

FIGURE 6

Quantity of biowaste and waste plastic recorded in the UK per annum

In the UK altogether 103.5 to 104.5 million tonnes of biowaste and waste plastic are produced from these sources. Green waste comprises that collected by local authorities and sent to composting operations. These data were provided by WRAP from a range of sources.[49] The uncertainty of adding together data from different sources should be noted.

31. There are, however, also additional sources of carbon-containing waste which might be used as a resource. Taken together, and including waste gases, these additional sources may be as large, or larger, than the 100 million tonnes reported above. For example, Water UK told us that one million tonnes of dry solids are produced from sewage sludge.[50] The Institute for European Environmental Protection told us that there may also be considerable amounts of crop and forestry residues which could be used:

"Crop residues are by far the largest in terms of availability. They are in the order of 122 million tonnes a year for Europe as a whole, versus around 40 million tonnes of forestry residues as a whole."[51]

32. British Airways told us that "up to €15 billion could flow into Europe's rural economy if all the available sustainable agricultural and forest harvest residues could be utilised."[52] We heard, for example, that 10 million tonnes of straw are produced in the UK each year, although there is debate as to how much of this could be diverted from existing uses.[53] Improved management of forests could deliver both an important source of local biomass and environmental benefits. In Britain, it has been estimated (making a number of assumptions) that if all existing broadleaf and conifer forests were brought into full sustainable yield production, and material not suited for use by existing markets was recovered, up to 4.2 million (dry) tonnes could potentially be made available.[54]

33. It is important to note that there is a difference between the amount of waste arising and the amount that could be used in a bioeconomy. The information provided above does not describe existing routes of treatment or distinguish between true wastes, co-products and by-products, although for some sources estimates of this are available.[55] Indeed, as a result of the way in which the data on biowaste is collected, much of it is already used. The spreading of manure to land, for example, is an important way of returning nutrients to the soil. We heard, however, that making use of waste in a bioeconomy to generate high value products does not necessarily eliminate an existing use. Anaerobic digestion can be used to treat manure to produce biogas and high quality digestate, which can be returned to soil. Although the economic feasibility would need to be examined, Professor James Clark told us:

"I am not too far away from Drax power station where the volume of biomass to be burned is staggering. I look at it and I think, "If you are going to burn it, then why can we not extract the chemicals first?" You can extract a lot of valuable chemicals in very large volume, given the volumes we are talking about, and calorific value is not affected. In fact, in many cases you can end up with a material that is easier to co-fire with coal, for example. I have always believed that for chemicals manufacturing we should sit alongside the energy industry, not try to compete with it but go alongside it, taking some of the higher value products, as we have learned from petroleum."[56]

34. In terms of characterising the amount of waste which may be available for use in a bioeconomy, it is also important to note that the UK exports considerable amounts of waste. This is discussed further in Chapter 3 of this report.

35. In addition to solid and liquid wastes, we also heard that waste gases from industry represent potentially important feedstocks for a bioeconomy.[57] A recent report from the Ellen MacArthur Foundation described carbon dioxide [CO₂] as a 'rough diamond.'[58] This report identified CO₂ as a high volume by-product of manufacturing processes, which could be transformed into valuable products using emerging technologies. This raises the possibility of moving from carbon capture and storage to carbon capture and reuse. The Government will need to be aware of this in developing future policies. During our inquiry, the Industrial Biotechnology Leadership Forum told us:

"Process gases from industry containing CO₂, CO and H₂are currently emitted to the atmosphere contributing to the carbon footprint of many companies, something that they are looking to reduce or avoid."[59]

36. Dr Colin Tattam, Director of Operations, Chemistry Innovation Knowledge Transfer Network, told us that considerable quantities of industrial gases were emitted in the North East of England:

"… process gases are an important consideration and there is an abundant supply. Anecdotal evidence says that there are probably about 10 million tonnes per annum out of the north-east alone, perhaps 30 to 40 across the UK per annum in total. That is an important consideration, and the very basic answer to your question is that capturing and translating that feedstock through to higher value products is not being done routinely on that scale right now."[60]

37. LanzaTech provided further information on waste gases from a range of sources.[61] They told us that gas from steel mills, for example, represents a potentially important feedstock for gas fermentation technologies:

"LanzaTech has evaluated in detail the potential for ethanol production from the UK steel industry. The two plants with the highest potential combined would yield over 300,000 tons (>100 million gallons) per year of ethanol from Basic Oxygen Furnace off gases alone. Blast furnace gases from all three UK mills have the potential to yield over a million tons per year (350 million gallons) of ethanol. Coke oven gases from UK steel mills and coke production facilities could add up to another 600,000 tons of ethanol (>200 million gallons)."

38. In addition, LanzaTech told us that waste gases from oil refineries, natural gas extraction and landfill sites could be used. Defra told us that in 2011, nearly 300 million tonnes of methane alone were emitted from industrial facilities, including landfill sites and the energy sector.[62]

39. It is important to note that the amount of many types of waste is declining. For example, the Technology Strategy Board, citing WRAP, told us that: "As an example, looking at the food waste 2010 figures for UK household waste totalled 12 million tonnes, with an additional 6.5 million tonnes through supply chain activities. By 2011 household waste had reduced by about 1Mt."[63] Solvert, a company specialising in the development of technology to produce renewable chemicals from sustainable raw materials, specifically the organic fraction of waste, noted that: "Although it is important to promote waste reduction and reuse it is not possible to eliminate waste at a national level."[64] WRAP echoed this point, stating:

"In the UK, 15 million tonnes of food waste is generated each year. While great efforts are being made to reduce the quantity of food waste being produced, for example through WRAP's Love Food Hate Waste campaign, there will always be an unavoidable portion of food waste (such as vegetable peelings, tea bags and egg shells) which cannot be reused and therefore must be treated."[65]

40. In the view of Dr Ed Green from Green Biologics, however: "There is lots of opportunity, even as waste arisings continue to drop, for investment opportunities, new technologies and so on." The Chartered Institution of Wastes Management (CIWM) told us that: "Waste composition and quantity is very far from static," noting that this is influenced by many different factors.[66] The CIWM also noted difficulties with accurately forecasting future waste composition. Declining or changing compositions of waste may pose a challenge for a waste based bioeconomy and it will be important that the available resource is effectively characterised and that technology is developed which is able to deal with changing waste streams. The Centre for Process Innovation (CPI) told us that in order to be future-proofed against declining waste streams:

"The most effective bio-economy process plants are designed with the flexibility to use more than one waste stream. This gives the plant operator the opportunity to select the most economically attractive or easily available feedstock. Without this flexibility in feedstock it is highly unlikely that bio waste based processes will be viable in the long-term."[67]

41. The information we received indicated that there are likely to be considerable amounts of waste which could be used as a resource in a bioeconomy. There is, however, no single source of this information and it has proved very difficult to get a clear picture of the quantities available for use. In our view, there is therefore an urgent need for improved information on the availability, quantities and quality of waste now and in the future. This is discussed further in Chapter 3 of this report.

Economic opportunity

42. During the course of this inquiry, we have heard that there are significant opportunities for the growth of a bioeconomy. We received a range of different estimates as to the contribution waste could make towards this. The Department for Business, Innovation and Skills (BIS), invited to supply information on the overall potential size of the bioeconomy, stated that while "the total value of the economic opportunity can only be an estimate … statistics suggest that we could be looking at a total economic market of around £100bn."[68] BIS estimates that transport biofuels alone could have a value of £60bn. Products derived from carbon-containing waste will form only a proportion of this total value of £100bn.

43. There is also a significant market for renewable chemicals, already estimated at $57bn worldwide and forecast to rise to $83 billion by 2018.[69] The UK chemical industry currently has sales of over £60bn per annum. The inquiry heard that around £6bn of this might be replaced with renewable chemicals produced from waste materials.[70] Professor James Clarke from the University of York noted:

"We calculated that the amount of organic carbon present in the food wastes, as calculated by the UN, is almost the same as the amount of carbon we [the world] use in all of the chemicals today."[71]

44. Dr Peter Williams from INEOS told us that bioethanol, derived from waste, could make a considerable contribution to the UK's transport fuel needs:

"… at the moment about 13 million tonnes of petrol is used in the UK, alongside diesel of course. If we look at the waste available, even engineered waste such as a solid-recovered fuel, probably about 25 million tonnes is available now. In principle, with the right technology approach, that could be converted into roughly 5 million tonnes of bioethanol. If we compare the 5 million tonnes to the 13 million tonnes, that can have potentially a material impact on fuel supply."[72]

45. Figures provided by the Department for Transport suggest that this could have a value of around £2.4 billion.[73] We also received evidence suggesting that a waste based bioeconomy has the potential to create skilled jobs, particularly in rural areas.[74] Dr Philp pointed to the importance of the chemicals sector to the UK. He noted that the job creation opportunities for products higher up the value chain, such as bio-based chemicals and other bio-materials, were greater than for biofuels and energy applications.

"Whilst environmental aspirations for the bio-based industries are important, the job creation possibilities are likely to be at least as important a priority for policy makers … For every job created in the business of chemistry in the US, 7.6 jobs are created in other sectors,[75] and on average they are high-paying compared to other manufacturing jobs. Meanwhile, modelling in Europe indicates that bio-based chemicals and plastics production can support many more jobs than biofuels and bioenergy applications. Carus et al. (2011) have estimated that materials use can directly support 5-10 times more employment and 4-9 times the value-added compared with energy uses, principally due to longer, more complex supply chains for material use."[76]

46. It has been estimated that if all sustainably available resources (agricultural residues, forestry residues and refuse derived fuel) in the EU were to be used for advanced biofuel production, in theory between 147 and 307 thousand jobs could be created across Europe, with 38 to 43% of these jobs primarily based in rural communities.[77] There is clearly a large amount of uncertainty associated with these estimates and such analysis makes a number of necessary assumptions in reaching these figures. During the inquiry, however, we also received estimates of the number of jobs which could be created by specific technologies or sectors. For example, the Anaerobic Digestion and Biogas Association told us that in the UK, 35,000 jobs could be supported in the anaerobic digestion sector.[78] British Airways told us that their Solena Greensky project "will provide approximately 1,000 construction jobs and 180-200 permanent jobs once in operation."[79] The Energy Technologies Institute told us that the gasification technology developed under their projects had the potential to sustain 2000 to 7000 jobs.[80] Meanwhile, Solvert told us that the technology they are currently developing to divert bio-waste from landfill into the production of high value commodity chemicals, has:

"the potential to create at least 32 waste to chemical facilities generating over £2 billion of investment, creating up to 1600 permanent jobs and over £300 million positive contribution to the balance of trade."[81]

47. We conclude that there are promising signs that a waste based bioeconomy could deliver substantial economic returns and support a considerable number of jobs. While there is clearly uncertainty in these predictions, it seems, however, that there is significant promise and the Government, industry and academia should take steps to further characterise this opportunity and ensure its full potential is realised.

Environmental opportunity

48. There are potential environmental benefits of using waste as a resource. It can divert bio-waste from landfill and capture waste gases, reducing greenhouse gas emissions. In addition, it reduces reliance on petrochemicals:

"The successful translation of research on utilising wastes and other feedstocks could help to reduce petrochemical use worldwide and help promote the use of renewables and potentially sustainable alternatives, contributing for example to reducing global carbon emissions."[82]

49. A major objective of the regulations relating to waste is to ensure its safe handling and to protect human health and the environment. Once a material is classified as a waste, it must be handled according to specific rules. The Environment Agency, who have responsibility for enforcing regulations on waste, told us:

"… as more material is diverted from landfill and there is greater financial incentive within the biowaste sector to take less proven materials and process greater volumes, there is an increasing risk of harm to soil and the wider environment."[83]

50. The Environment Agency noted, for example, a relatively high number of pollution incidents associated with waste permits for anaerobic digestion facilities. This illustrates the need to ensure that appropriate measures are put in place when making use of waste. The Environment Agency have been working on 'End of Waste' quality protocols, to help simplify the regulatory process associated with transforming a waste into a product. The continued development of such protocols, which reduce the regulatory burden of handling waste, whilst simultaneously ensuring environmental protection, will be important for enabling waste to be used as a feedstock for the bioeconomy.

51. The environmental benefits of using waste as a feedstock will vary on a case by case basis. It will depend on factors such as the environmental impacts associated with the current route of disposal or use, the energy required to transform it into a product, and the energy costs of transporting the waste to a site where it can be used. One of the central aims of a bioeconomy is to reduce greenhouse gas (GHG) emissions and so it is important that technologies deliver a positive greenhouse gas balance. As noted by the Industrial Biotechnology Leadership Forum:

"Use of waste as feedstock reduces the amount going to landfill or escaping process facilities and therefore inherently is viewed more environmentally viable. However, all cases must be considered on an individual basis. The environmental viability and benefit needs to also consider logistics & transport, energy to process and end of life aspects i.e. the whole life cycle. However, the majority of LCA studies using lignocellulosic feedstocks in the production of chemicals demonstrate environmental benefits over petrochemical derived counterparts."[84]

52. Life Cycle Assessment (LCA) is a methodology used for systematically evaluating the environmental footprint of a product through all stages of its life cycle. It can be used to compare the environmental footprint of using different feedstocks or processes to generate products. The evidence we received suggested that there are environmental benefits associated with specific technologies or facilities. Virgin Atlantic told us that the technology they are developing with LanzaTech for producing aviation fuel from waste gases is anticipated to result in much lower greenhouse gas emissions:

"Initial Life Cycle Analyses suggest that the resulting biofuel will emit 60% less carbon than the fossil fuel it will replace, kerosene. Moreover, because it uses a waste-stream, it creates a biofuel that does not impact on land use or food production."[85]

53. INEOS Bio also indicated that the LCA for a specific, proposed project on Teesside was estimated to have lower GHG emissions than alternative approaches for using waste:

"The Eunomia life cycle GHG report for the proposed Seal Sands, Teesside plant confirms that producing biofuel from waste would be an environmentally sensible use of the waste as a resource compared to the alternatives, including composting, anaerobic digestion and biomass CHP."[86]

54. We also heard that there are limitations to LCA and outputs can be quite variable.[87] Dr Philp drew attention to an LCA of 60 bio-based chemicals, noting that the majority saved greenhouse gas emissions. He also observed, however, that it was difficult to predict the exact savings with accuracy and stated that: "I do not think the LCA is inaccurate. I think it is to do with the boundaries. One of the things we have said is that internationally we need to get this harmonised." Professor Murphy, an expert in LCA from the University of Surrey, agreed that there are limitations to LCA and explained how it should be used:

"LCA is a good tool when you have reasonable data and clear and transparent system boundaries, you know what your question is at the beginning of the analysis and you have a very clear and transparent goal and scope. Then it works really well and it is entirely possible to do formal uncertainty analysis within an LCA, either by using measures of variation in the data or by doing scenarios and sensitivity analyses, which any good LCA is obliged to include according to the ISO standard in order to test the reliability or the reproducibility of the result when you vary important parameters."[88]

55. Professor Greg Tucker from the University of Nottingham noted that their LCA for converting wheat straw into ethanol delivered:

"varying feedback on how much greenhouse gas emissions would be reduced, ranging from about 10% to about 30%. They all show positive reductions but how positive is quite a wide range, and I think it does rely on the accuracy of the evidence you are putting in as to how certain you are, and on the efficiency of the model that you are using."[89]

56. Professor Murphy noted that a positive greenhouse gas balance was less likely to be seen if co-products and by-products were diverted away from an existing use.[90] It will be important to take this into account, and to develop agreed standards for LCA, which allow different products and processes to be compared.

57. Although it can be difficult to provide a precise evaluation of environmental impacts, the evidence we received suggested that in general there are environmental benefits from making use of waste as a resource. We conclude that more consistent approaches for analysing environmental benefits are needed so that the size of the opportunity can be better understood. This is discussed further in Chapter 3 of this report.

24 Dr Philp, OECD (acting in a personal capacity). Back

25 IBLF, Q 67 (Professor Clark, University of York Green Chemistry Centre). Back

26 LanzaTech, Virgin Atlantic, Dr Philp, Q 16 (Professor Tucker). Back

27 LanzaTech, Government supplementary evidence. Back

28 Government. Back

29 Q 45 (Professor Hunter). Back

30 RCUK, University of Nottingham, LanzaTech, Virgin Atlantic. Back

31 LanzaTech. Back

32 The Technology Readiness Level (TRL) describes the stage of development of a technology from basic idea, through discovery and research, innovation and finally commercialisation. Demonstration scale is a stage immediately prior to commercialisation. Back

33 Dr Philp, OECD (acting in a personal capacity). Back

34 The integrated biorefinery concept. See: http://www.nrel.gov/biomass/biorefinery.html. Back

35 Royal Society of Chemistry. Back