Being Sustainable in Unsustainable Environments

As environmental sustainability entered mainstream understanding, organizations began to issue sustainability reports in the s. Environmental indicators, such as carbon emissions and energy consumption, became mainstream business indicators, and they were much easier to measure than social performance indicators. The surge in international attention, the growing body of environmental legislation and the sharp increase in environmentally-focused sustainability reporting meant the environment became the primary focus of many sustainability conversations.

If organizations make sustainability solely about the environment, what opportunity cost do they suffer? And what do all those benefits have in common? Each of them is essential to running a truly sustainable business—one that will stand the test of time. Leading, truly sustainable businesses operate in harmony with communities, attract and retain talent, identify and manage risk, build meaningful relationships with customers, and improve bottom line performance with motivated, satisfied and dedicated employees under responsible governance.

First, we must measure economic, environmental and social performance across the whole organization, including down its supply chain. Second, we must understand which are the most material indicators to our organization. Third, we must define plans, programs, policies and processes to address risks and seize opportunities to improve across all these material impacts.

And fourth, we need to talk about it. Some studies have found high efficiencies of removal of nitrogen and phosphorus from wastewater containing manure Gonzalez et al. Algal biofuel systems have the potential to increase water quality and to promote municipal or agricultural wastewater treatment systems with improved sustainability.

However, the maintenance of lipid-rich strains and the manipulation of growth conditions to promote high lipid production have yet to be demonstrated consistently for outdoor pond systems, including wastewater treatment ponds DOE, b. Industrial wastewaters have lower nutrient concentrations and higher toxicant concentrations, and thus are less likely to be used to generate the algal biomass necessary for commercial-scale production of biofuels Pittman et al. Integrated algal biofuel production systems can remove many other pollutants, such as metals and organic contaminants, including endocrine disruptors Mallick, ; Munoz and Guieysse, ; Ahluwalia and Goyal, ; DOE, b.

Whether pollutant uptake by algae is desirable depends on whether coproducts are to be produced with algal biofuels or whether the lipid-extracted algae are to be used for nutrient recycling. Pollutant removal by these systems would improve water quality, but it also could pose a potential risk if organisms such as migrating waterfowl directly or incidentally consumed high metal content algae during the cultivation process, or if humans or wildlife were exposed chronically to the dried algae during biomass processing.

Uptake of pollutants by algae is not desirable if residual biomass is to be used for human cosmetic products or animal feed.

Sustainability is a three-legged stool

The pathways described in Chapter 3 affect the types, probabilities, and magnitudes of water-quality effects Table For example, slow releases of nutrients to natural environments and increased potential for eutrophication and groundwater pollution are common for open systems but not for closed systems. Herbicides likely would be used only in open systems. The water quality benefit for wastewater treatment is achieved only if wastewaters are used as nutrient sources, but the scenarios in Chapter 3 do not specify this. Open-pond, salt water, producing FAME a , recycling nutrients and water.

Open-pond, salt water, producing biomass, pyrolysis, recycling some nutrients and water. Slow releases from seepage, overtopping likely, catastrophic breaches rare. Herbicides, heavy metals may be present and pose occupational or ecological exposures and risks. Proposed sustainability indicators for water quality include aqueous concentrations and loadings of nutrients, herbicides, metals, and salinity of groundwater GBEP, These indicators are standard measures for quality of water and wastewater Eaton et al.

Concentrations of nutrients are included because they relate to benefits or potentially adverse effects on water quality for example, eutrophication. These usually are measured quantities, and baseline levels and natural variability also can be measured. Loadings are field measures or simulation results representing the contribution of released algal biofuel culture media to receiving waters.

These may be compared to other loadings to those waters. Good design and engineering would minimize the potential for releases of water and nutrients from open-pond systems to surface water and to ground water. Toxicant concentrations for example, metals need to be characterized, particularly if wastewater or produced water is used as culture medium. Information on the nutrient removal efficiencies of commercial-scale facilities would be needed if algal biofuel production is to be combined with wastewater treatment.

Land-use change is a change in anthropogenic activities on land, which often is characterized in part by a change in land cover, including the dominant vegetation.

Land-use changes play a role in the sustainability of algal biofuel development because of associated environmental effects, such as net GHG emissions, changes in biodiversity, and changes in ecosystem services such as food production. Moreover, there is growing societal concern about the spatial and temporal scales of some types of conversions, such as deforestation and urbanization. The impacts of algal biofuel development will depend in part on the type of land conversion, the extent area of land use that has changed, the intensity of land disturbance and management, and the duration of the change for example, whether it is reversible.

Commercial-scale production of algal biofuels will require substantial land area for each facility see Chapter 4 , and the large-scale deployment of algal biofuels will lead to conversion of lands from other existing uses. Land conversion for ponds, processing facilities, and refineries for most products will be localized, and potential land conversion for related infrastructure, such as roads and power lines to the facilities, will be more diffuse and will involve linear features. This section focuses on land-use change LUC associated with algae cultivation, because change associated with feedstock processing or refining facilities is not different in kind from that of other liquid fuel sources.

High-value lands used by agriculture, by other commodity industries, and for residential purposes are unlikely to be used for algae cultivation because algae cultivation does not require fertile soils and because capital and operating costs would have to be kept low for algal biofuel companies to operate close to the profit margin Table Similarly, the conversion of forestland is unlikely because of the high costs of clearing and site preparation and the high value for residential or recreational use.

Land-use change for algal biofuels is. On coasts, dredge spoil islands might be additional options for use. For example, Phycal, an algal biofuel company, is using fallow land in Hawaii that was previously a pineapple plantation but is no longer economically viable for that use. Sapphire, another company operating in the Southwest, plans to develop nonagricultural land for algae cultivation.

Siting requirements are described in Chapter 4. Competing land demands could change over time and may influence the landscape of algal biofuels. For example, some of the same lands that are attractive for algal biofuel development are also attractive for large-scale solar power development BLM and DOE, Direct land-use change generally is defined as a direct cause-and-effect link between biofuel development and land conversion in the absence of strong external mediating factors. Direct land-use change occurs within the biofuel production pathway when land for one use is dedicated for biofuel production.

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However, in practice, direct land-use change from biofuel production generally is assumed to include lands used for feedstock production, processing, storage, and refining areas. Indirect land-use change occurs when biofuel production causes new land-use changes elsewhere domestically or in another country through market-mediated effects NRC, Direct land-use change can result in carbon sequestration or net GHG emissions, depending on the type of land conversion and prior land use. For example, converting from annual-crop production to perennial-crop production can enhance carbon storage on that piece of land Fargione et al.

Conversely, clearing native ecosystems to produce row-crops would result in a one-time release of a large quantity of GHGs into the atmosphere Fargione et al. Perennial pasture is effective in sequestering carbon in soil Franzluebbers, ; Gurian-Sherman, Removal of such vegetation would result in a one-time loss of carbon and the elimination of any potential for further carbon sequestration if the land is to be left as a pasture. In contrast, if the algae cultivation ponds are installed on degraded land that is not storing much carbon, immediate emissions from the conversion will be minimal.

Indirect land-use change could occur if the use of land to cultivate biofuel feedstocks replaces and ultimately reduces the production levels of crops destined for a commodity market. The lowered production of those commodities could drive up market prices, which in turn could trigger agricultural growers to clear land elsewhere to grow the displaced crops in response to market signals Babcock, ; Zilberman et al. However, as stated above, because algal feedstock cultivation does not require fertile cropland, arable land likely will not be used for algal biofuels Sheehan et al.

In addition, protein from lipid-extracted algae potentially can replace soybean or other terrestrial crops as feedstuff Wijffels and Barbosa, and reduce the demand for land by terrestrial crops. The nutritional compatibility of algal feedstuff and the animal diet would have to be examined.

Pasture and rangeland could be converted to algae cultivation, and displacement of these land uses by algae also may or may not result in other indirect effects. If the pasture or rangeland is surplus and not in use, then repurposing the land will not incur indirect land-use change ILUC.

In contrast, if algae cultivation displaces grass-fed cattle production, producers might decide to change to corn-fed cattle production. Changing from grass-fed to corn-fed cattle production also would exert pressure on the corn-grain market.

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Alternatively, if existing pasture and rangeland is limiting beef production, such that removing some of this land would decrease production, then grass-fed cattle production might be replaced elsewhere. The indirect land-use changes not only affect ecosystem services, but result in changes in GHG emissions that have to be considered in life-cycle GHG assessments for algal biofuels. If the indirect effects of algal biofuel production are to be quantified, then the potential biodiversity, water quality, and water balance impacts would include those associated with indirect land conversions.

Previous quantification of indirect effects of biofuels generally has been limited to GHG effects and food security effects. As in the case of terrestrial-crop biofuels, market-mediated indirect land-use changes are difficult to ascertain, and estimates of associated GHG emissions are highly uncertain NRC, Although complex models have been used to project the extent of indirect land-use changes as a result of terrestrial-crop biofuels, the committee is not aware of similar projections for algal biofuels.

Algae cultivation is less likely to incur indirect land-use changes because it does not require prime agricultural land. Converting crop lands to new crops algal biofuels also will require new ownership or a willingness on the part of farmers to grow a new commodity. Growing algal biofuels will require differing work schedules than row crop farming.

Even if cropland is not to be converted to algal ponds, the above discussion of potential pasture conversion illustrates a potential for indirect land-use change. With respect to land-use change, the primary relevant difference among the pathways in Chapter 3 is the difference between the land required for open-pond and photobioreactor systems see Chapter 4. The spatial and temporal scales of land-use change would be commensurate with those of land use. In general, algal biofuel development will avoid forestland and land with agricultural value. Avoiding pastureland and areas of high biodiversity or recreational value also would eliminate some of the sustainability concerns associated with commercial development of algal biofuels.

Land-use change is not consistently proposed as a criterion for sustainability, even though it often is considered a factor influencing aspects of the sustainability of biofuel for example, GHG emissions, biodiversity, water quality, and soil quality. Therefore, some compilations of sustainability indicators do not include indicators of sustainable land use for example, McBride et al. However, there are aspects of land use, such as infrastructure, impervious surfaces, and some disturbances, that may be long lasting or irreversible and may not be adequately considered using indicators of other categories of sustainability.

Potential indicators of sustainable land use include percent impervious surface Sutton et al. Changes in impervious surface area affect the water cycle and watershed dynamics, as well as terrestrial and aquatic habitats. The area of land disturbed can be considered a measure of sustainability. Land disturbance areas can be normalized based on a land-condition factor Eq. Table shows examples of land condition factors that can be multiplied by disturbed area to give a currency of disturbance. Reprinted with permission from Elsevier. Land condition factors are multiplied by disturbance area to allow comparison of disturbed areas of different intensities and scales.

Trends in land-use change related to algal biofuel production are important to quantify.

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However, until there is a history of commercial development of algal biofuel production facilities, probable land-use changes and trends will need to be projected based on economic and social drivers and environmental contributing factors. Where important or rare ecosystem services are provided by the baseline land use, a measure of those services could serve as a sustainability indicator for algal biofuels. The services of pastures, rangelands, and coastal waters that might be displaced by feedstock production facilities would be important to quantify.

Relevant metrics would be:. A less direct indicator of livestock numbers or biomass would be area covered by grassland and shrubland West, ; The H. Additional sustainability indicators have been suggested for brownfield redevelopment efforts. Some of these are summarized in Wedding and Crawford-Brown and would be appropriate where algal biofuel production is sited on brownfields.

The potential to mitigate GHG emissions is one of the motivations to develop biofuels. The basis of mitigation is that carbon emissions from combusting a biofuel are cancelled by the corresponding capture in photosynthesis. This said, the net GHG emissions of producing biofuels and coproducts are not zero because of carbon and other GHGs emitted in processing. Primary GHG emissions from algal biofuels are expected to be connected to the use of energy in the processing chain see section Energy in Chapter 4. The translation of energy use to GHG emissions is complicated by variability in the carbon overhead of different forms of energy, in particular electricity.

Depending on the mix of fossil fuels, hydropower, nuclear, wind, and other sources providing power to the grid, emissions vary by state from 13 to 1, grams CO 2 equivalent per kilowatt hour EIA, The approach taken by many analysts is to use a national average emission factor Liu et al. LCA results for net GHG emissions for algae biofuel production vary from a net negative value that is, a carbon sink to positive values substantially higher than petroleum gasoline Table As with the case for energy use see Chapter 4 , drivers of variability in CO 2 emissions are nutrient source, productivity and process performance, and the credit associated with coproducts.

For example, Sander and Murthy assumed that residual algal biomass substitutes for corn in ethanol plants. Corn is energy intensive to produce; the. The direct carbon emissions of driving an average gasoline automobile is about 0. GHG credit from replacing corn with oil-extracted algae as a feedstock for ethanol results in a negative carbon balance.

For reference, the direct carbon emission of combusting gasoline is about 2. The vast differences in results in Table , ranging from a net carbon credit to emissions far larger than those from petroleum-based diesel, present a challenge for interpretation. Differences in nutrient sourcing and coproducts are treated via four scenarios: The common coproduct system used is generation of bioelectricity from gas generated by anaerobic digestion with the electricity generated substituting for carbon emissions from the U.

Table shows the ranges in results from the six treated studies, after normalization, for the four scenarios. These meta-analysis results suggest that the CO 2 source and coproducts are critical factors in the GHG balance. It is, however, premature to conclude that algal biofuels based on recycling CO 2 and producing biogas has net negative GHG emissions.

The variability in Table is based on differences in energy data and assumptions in the six existing studies. It is not yet clear if current LCA analyses of algal biofuel production systems will accurately reflect the energy use of a real-world, scaled-up system. None of the studies above addresses the potential issue of indirect land-use change from biofuels. As stated earlier, it is possible that conversion of pastureland to algae cultivation facilities would necessitate conversions to pastureland elsewhere.

However, uncertainties are too great to quantify this probability or to calculate net GHG emissions under these assumptions. See section Land-Use Change in this chapter. While many agricultural processes emit non-carbon GHGs such as nitrous oxide N 2 O and methane Weber and Matthews, , these emissions have not been established empirically as significant for algae cultivation. N 2 O could be emitted from cultivation systems, and these emissions would need to be quantified in the future for cultivation conditions that might promote N 2 O or methane emission.

One study of a single species quantified N 2 O emissions from algal culture under laboratory conditions Fagerstone et al. In this study of Nannochloropsis salina with nitrate as a nitrogen source, elevated N 2 O emissions were observed under a nitrogen headspace photobioreactor simulation during dark periods, but N 2 O emissions were low during light periods.

In contrast, when the headspace consisted of air open-pond simulation , N 2 O emissions were negligible. Denitrifying bacteria were present. Denitrification is the microbial reduction of nitrate and nitrite with generation of N 2 O and, ultimately, gaseous nitrogen. Anaerobic environments are required for the transformation, but high rates of denitrification occur where oxygen is available alternately, then unavailable Kleiner, In rivers, ponds, lakes, and estuaries, the production of N 2 O is correlated with nitrate concentrations in the water Stadmark and Leonardson, Whether anaerobic denitrification is the only potential pathway for N 2 O generation in algal cultivation systems is unclear.

Weathers has shown that certain Chlorophyceae in axenic culture evolve N 2 O when using nitrite as a nitrogen source. They speculated that oxidation of ammonium NH 4 by bacteria was the likeliest N 2 O-generation pathway under the observed aerobic conditions. Proper management of the algal cultivation systems, which would prevent senescence of algae and maintain aerobic conditions in ponds, likely would keep N 2 O emissions to low levels.

Methanogenesis can occur in freshwater and marine sediments, waterlogged soils, marshes, and swamps where oxygen is low. These conditions might prevail in some ponds with substantial biomass or other organic matter in the sediment. Methane is released when organic acids, alcohols, celluloses, hemicelluloses, and proteins are degraded. Methane production is related to water temperature Stadmark and Leonardson, and is maximized at neutral pH Alexander, Methanogenesis is suppressed by nitrogen compounds that bacteria can use as electron acceptors, including nitrate and nitrite Bollag and Czlonkowski, , but these compounds may be reduced easily in oxygen-depleted environments.

Methanogenesis and denitrification might be enhanced if the culture fails. During catastrophic failure of the culture, the dense algal cultures in algal biofuel ponds can become anaerobic and emit a variety of volatile nitrous or sulfur compounds as well as methane. However, culture failures would be expected to be short-term and rare occurrences if algal biofuel companies are to maintain a profit margin.

The opportunities for mitigating energy use discussed in the section Energy in Chapter 4 apply to reduction of GHG emissions. There is additional potential to mitigate GHGs by using low-carbon energy sources for processing and by substituting for carbon-intensive coproducts. For example, the carbon benefit of generating bioelectricity is larger in areas where the grid relies on fossil fuels.

The yields for producing and properties of different coproduct options are poorly understood. The potential for N 2 O and methane emissions could be reduced through thorough mixing and proper management of algae cultivation Fagerstone et al. The data gaps for estimating energy use and the method gaps in reducing energy use discussed in the section Energy Chapter 4 apply to reduction of GHG emissions.

An appropriate sustainability indicator for GHG emissions is the amount of CO 2 equivalent emitted per unit energy produced, which has been selected as an indicator for GHG emissions of biodiesel and commonly has been used in discussing energy-related GHG emissions GBEP, ; Mata et al.

The introduction of large bodies of water in arid or semi-arid environments could alter the local climate of the area by increasing humidity and reducing temperature extremes. Similarly, the introduction of large-scale, open-pond algal cultivation systems in arid or semi-arid environments, where much of algae production in the United States is projected to take place see Chapter 4 , could affect local climate and ecosystems.

The use of photobioreactors would not likely alter local climate. Studies of reservoirs provide some useful ecological information. Reservoirs created by the damming of rivers could affect evaporation rates of the surrounding landscape, leading to changes in vegetation cover and terrestrial species diversity Huntley et al. Large dams can affect surrounding climate and precipitation, particularly in Mediterranean and semi-arid climates Degu et al. The sustainability indicators for potential changes in local climate are trends in relative humidity and trends in temperature distribution statistics.

While parallels can be drawn from the introduction of large reservoirs in arid regions, the variability in size, geography, and production methods that will emerge as the algae industry grows will necessitate additional research to fully understand and address the impacts associated with local climate alteration.

The air quality impacts of algal biofuel production will depend on system design. Different air quality issues arise in conjunction with the different steps of the algal biofuel supply chain. Thus, this section is organized by the steps along the production pathways. The wide range of potential organisms for producing algal biofuels and the wide range of final fuel products result in a broad range of possible air emissions.

This section focuses on the air quality emissions unique to algal biofuel production and does not consider emissions of fossil fuels used to power processing equipment or emissions of fossil fuels that may be used in manufacturing fertilizer or pesticides. The purpose of the chapter is to consider emissions unique to algal biofuel production so that appropriate indicators are identified.

However, emissions from fossil fuels used along the production pathway of algal biofuel would need to be considered in any LCA of the airquality impacts of different algal biofuel designs. Further, how algal biofuels will be scaled up and how air quality might change with increasing scale is uncertain. The committee is not aware of any measured emissions of atmospheric pollutants from algal biofuel feedstock ponds published in the literature.

Under normal running conditions in open ponds, the cultures are aerobic, and low emissions of volatile organic compounds VOCs are expected Rasmussen, ; A. However, macroalgae and microalgae growing in natural marine environments are known to be important sources of VOCs, including isoprene and monoterpenes Giese et al. Three of the species tested are being grown for biofuels in open raceways, open ponds, and closed photobioreactors, with test samples derived from cultures being grown in treated wastewater with CO 2 enrichment.

In preliminary findings, 45 VOCs have been identified P. Other emissions expected are aerosols that may be emitted directly or created in the atmosphere through reactions of gaseous emissions of precursor gases of sulfur dioxide SO 2 , nitrogen oxides NOx , NH 3 , and VOCs.

Aerosols could include algae and nutrients, as well as a wide range of compounds that are produced by microalgae, including toxins. See section Pathogens and Toxins later in this chapter. Microalgae in the natural marine environment are known sources of sulfate aerosols for example, Liss et al. A large number of algae produce odorous secondary metabolites reviewed in Smith et al. The odors are produced during aerobic growth as secondary metabolites. Other odorous compounds are associated with the decay of algae under anaerobic conditions where bacteria break down the organic material and produce hydrogen sulfide and NH 3 , both of which have a strong odor.

In open ponds intended for algae cultivation, anaerobic conditions are minimized. Emissions from photobioreactors would be lower than those from open ponds if undesirable gaseous products and odorous chemicals are scrubbed before gas exchange with the outside environment is permitted. Drying processes may produce coarse and fine particulates, including algae and lysed algae.

The concentrations of particulates in air will depend on the technologies used; for example, belt dryers and convective systems will lead to greater local emissions than passive solar drying. Whether emissions move beyond the facility will depend on the level of containment. Particulates could be an occupational hazard even in closed facilities. In confined areas, dust could be an explosion hazard. Poor drying methods also can give rise to decomposition of biomass and release of VOCs, amines, methane, and other compounds. Most proposed algal biofuel processing methods involve extraction of lipids or other compounds from cells using organic solvents.

Extraction with organic chemicals, by necessity, results in some solvent emissions, and the quantities emitted depend on the technology applied. The most common solvent that is openly discussed by manufacturers is hexane Demirbas, ; Lardon et al. In an environmental assessment, Sapphire Energy, Inc. Desirable properties of these solvents are low cost, recoverability, low toxicity, nonpolar structure, and poor extractor of non-lipid cell components Rawat et al.

Hexane is used as an extractant of vegetable oils in biodiesel production with fugitive hexane emissions Hess et al. Compliance with regulatory standards likely would minimize release of solvents. Technologies to convert total biomass to drop-in liquid fuels are being tested. These processes may have additional feed inputs and will have different air emissions from those from production of esterified or green diesels. Pyrolysis of biomass yields three energy products—solids char , liquids bio-oils , and gases—in various proportions depending on the temperature, pressure, residence time, and other factors.

The gases are recycled to provide energy for the system and thus do not contribute directly to air emissions except for any fugitive emissions that might escape the system. The heating of the pyrolysis units might contribute a small amount of NOx and carbon monoxide CO. Additional energy, likely supplied by natural gas may be required to sufficiently dry the algal biomass prior to pyrolysis.

Particulate emissions, acid gases, and hydrocarbon emissions from pyrolysis are not characterized in the literature. The bio-oil produced from whole-cell pyrolysis will require additional upgrading to produce transportation fuels. The upgrading can be done with a separate hydrotreating step or a process similar to the Integrated Hydropyrolysis and Hydroconversion process.

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In either case, input of hydrogen is required. The production of hydrogen produces low levels of NOx Spath and Mann, and makes a CO 2 stream that could be used to supply the algae cultivation. Anaerobic digestion for processing wastewater from algal biofuel production facilities is described in Chapter 2. NH 3 has been observed to be present in biogas from anaerobic digestion at concentrations up to ppm Schomaker, The concentration of NH 3 in biogas would depend on the nitrogen content of the particular feed material. Early work by Golueke et al. NH 3 would not be released to air around the facility because of the desire to recycle nutrients required for cultivation.

The primary categories of environmental effects associated with the end use of biofuels in vehicles are evaporative emissions and tailpipe emissions from fuel combustion. Fischer-Tropsch F-T synthesis converts a mixture of CO and hydrogen which may be derived from biomass into liquid hydrocarbons. Generally, the type and quantities of emissions vary depending on fuel characteristics for example, chemical properties and blends , age of the vehicle or other equipment, power output of engine, operating condition of engine, how the vehicle or other equipment is operated, and ambient temperature Graham et al.

Using biofuels in place of petroleum-based fuels decreases emissions of some air pollutants while increasing others Table ; NRC, EPA established emission standards for tailpipe emissions of CO, hydrocarbons, NOx, and particulate matter to which vehicle manufacturers and refiners have to comply EPA, a. Emissions of air pollutants need to be assessed over the life cycle of algal biofuels and compared to petroleum-based fuels and other alternatives. The Hill et al.

They found that although the uses of gasoline and terrestrial-plant biofuels corn-grain ethanol and cellulosic ethanol release similar amounts of VOC, PM, NO x , SO x , and NH 3 , emissions from the production stages are significantly different between petroleum-based fuels and biofuels. The committee is not aware of any LCA of such air pollutants for algal biofuels. Such analysis is critical in assessing whether biofuel production and use result in air quality improvement compared to fossil fuel and it provides information on stages in the supply chain that are key contributors to air pollutants.

Particulate emissions, hydrocarbon slip, and acid gases all possible from combustion of off-gas. With respect to air quality, the differences in expected effects among the pathways in Chapter 3 depend on the type of culture system open versus closed , the drying process, and whether or not extraction and pyrolysis steps are present in the pathway Table Algae produce a number of aerosols and secondary metabolites, some of which may be noxious for example, malodorous or harmful to humans.

Similarly, some supply-chain processes, such as extraction and drying, may emit solvents or particulates that could affect local air quality if not contained. If an algal biofuel facility is located near human populations, measures likely will be taken to contain or limit the release of any products that negatively affect local air quality or are perceived to be a risk to public health.

The health costs of some types of air emissions were discussed in Hill et al. Depending on the quantity of these outputs, and the proximity of population centers to a production facility, the reduction in air quality and perceived health and quality-of-life risks may impact the. If the public is not made aware of these potential effects prior to the siting and permitting of a facility, there is a risk that the production of undesirable compounds will be viewed as unacceptable after the construction of the facility has been completed.

If this is the case, litigation or protests may slow or shut down operations, resulting in financial losses for the developer and negative attention for the industry at large. The more contained a process is, whether it is the biomass cultivation process, drying, solvent extraction, pyrolysis, or digestion, the lower the emissions to air will be. Therefore, photobioreactors could have reduced air-quality impacts compared to open-pond systems.

Rather than recognising that all human activity has impacts and taking responsibility for them, sustainability accounting uses a limited set of performance indicators which can obscure the real issues. Competing organisations in any sphere, from retail stores to governments, vie to be more sustainable than each other.

We see social media discussions about "sustainable leadership" or how to "leverage sustainability" in business. All of which seems to me to be utter baloney. Meanwhile a lucrative new industry has grown up around "sustainability consultancy" — whatever that means.

The Oxford English Dictionary defines sustainability as "the property of being sustainable". It also defines "sustainable" as "to be capable of enduring", which should be enough for us all to want to be sustainable — consider the alternative: If any activity is not sustainable, from a single business to an entire economy, it will cease. A leader who fails to lead a business or country sustainably will bring about its demise. This is not a question of degree.

There is no "more sustainable" or "less sustainable". The only variable is how long the organisation or activity can survive. The Oxford English Dictionary also defines the term "environmental sustainability" as "the degree to which a process or enterprise is able to be maintained or continued while avoiding the long-term depletion of natural resources". So environmental sustainability is a property of a system or rate of activity, such as constructing buildings or consuming fuel.

This makes it clear that sustainability is inherent to the system or activity as it surely cannot be added afterwards through political or corporate leadership. The Bruntland Commission muddied the water further by providing a definition of "sustainable development" as "development that meets the needs of the present without compromising the ability of future generations to meet their own needs.

However, this subtle distinction has been long forgotten by those who consider that economic growth is a prerequisite. So development has become synonymous with continual economic growth and sustainability accounting is used to convince us that it can be achieved benignly, in the face of all the evidence.