Algae bioenergy - The Sustainability Management Wiki

Authors: Lennard Schulte and Sophie Schulz
Edited by: –
Last updated: May 16, 2026

Executive summary

Microalgae can produce fuels and other energy carriers with high areal productivity and without directly competing for arable land. Organizations are exploring algae because cultivation can pair energy production with additional services such as CO₂ utilization and, in some designs, nutrient removal from wastewater.

Commercial algae cultivation began with high-value products (for example, pigments and omega-3 ingredients) because these markets can absorb higher production costs than fuels. For fuels, the core technical choices are open raceway ponds, closed photobioreactors, and hybrid two-stage systems that combine controlled growth with a stress phase that boosts lipid accumulation. Across all designs, harvesting and dewatering remain major cost drivers because biomass concentrations are low and large water volumes must be processed.

Economic performance is still the main barrier to large-scale fuel deployment. Capital-intensive infrastructure, ongoing nutrient and CO₂ supply, and energy use in separation and processing keep costs above competing fuels. As a result, many business cases rely on a biorefinery approach that sells multiple co-products and uses higher-margin specialty markets to cross-subsidize energy outputs.

Ecological performance varies widely across studies because results depend on electricity supply, harvesting choices, and nutrient sourcing. Life-cycle assessments consistently identify energy-intensive separation and drying as key hotspots, while fertilizer production and nutrient losses can drive upstream emissions and eutrophication impacts. Designs that use low-carbon electricity, avoid unnecessary drying through wet conversion pathways, and recycle nutrients (including wastewater-derived nitrogen and phosphorus) generally show better environmental outcomes.

Social acceptance is typically conditional: stakeholders often view algae fuels as promising but uncertain, and concerns increase when genetic engineering or marine farming raises biosafety and local-use conflicts. Policy frameworks therefore matter. Long-term R&D and demonstration support, credible lifecycle-performance standards, and carbon-pricing or low-carbon fuel policies can reduce investor uncertainty and steer innovation toward verifiable emissions reductions rather than volume-only expansion.

1 Description and history

Microalgal bioenergy is attracting increasing scientific and political attention due to its high productivity, versatile conversion pathways, and potential contribution to sustainable energy systems. The first isolated algae culture (Chlorella vulgaris) was established in 1890 by Beijerinck for basic research purposes. In 1919, Otto Warburg used algae to study plant physiology, as they function as compact model organisms for photosynthesis. While both researchers primarily employed algae as research tools, large-scale mass production did not begin until after 1948, when research centers were established around the world in cities such as Stanford, Essen, and Tokyo. John Burlew summarized these developments in a major standard work in 1953.¹ Building on these results, commercial cultivation began in the late 1960s, focusing on niche markets. Algae were used for aquaculture feed, but the main economic driver was the production of high-value ingredients such as pigments and antioxidants. Different species were cultivated for specific applications, including Chlorella and Spirulina for health foods, Dunaliella salina for beta-carotene, and Haematococcus pluvialis for astaxanthin. Open ponds with paddle wheels formed the technical basis of early large-scale cultivation. However, in addition to high material costs, fundamental biological and physical constraints limited productivity. These constraints are primarily related to light availability, as dense cultures suffer from mutual shading and light limitation.¹ Increasing reactor depth or tube diameter further reduces light penetration and may lead to photoinhibition in surface layers. Attempts to optimize light utilization, such as reducing antenna size, have so far only partially addressed these limitations. Moreover, relatively slow growth ties up capital and reduces economic efficiency.²

As algae cultivation developed further, two main techniques became established: low-tech raceway ponds and the technologically sophisticated photobioreactors. Raceway ponds are open basins equipped with large paddle wheels that circulate water, preventing the algae from sinking and enabling them to reach the light. However, their open design makes them highly susceptible to contamination by bacteria and other species, and CO₂, which algae need for growth, can easily escape. In contrast, closed photobioreactors allow precise control of environmental conditions under laboratory-like settings but significantly increase capital and operational costs.² As an intermediate solution, hybrid two-stage cultivation systems were developed. In the first stage, algae are cultivated in closed reactors under optimal conditions to achieve high cell density. Practitioners often call this the “cultivation phase.” In a second stage, the dense culture is transferred to open ponds and subjected to nutrient stress, reducing growth while promoting lipid accumulation. The resulting oil-rich algae can then be harvested. However, harvesting represents a major cost factor, accounting 20–30% of total production costs. A key challenge is the very low biomass concentration in open pond systems, which results in strong dilution effects.³ Consequently, large volumes of water must be removed through energy-intensive processes such as centrifugation and filtration, significantly increasing operational costs.⁴ Flocculation is often applied to aggregate cells before dewatering into a concentrated slurry.³

The transition to biofuel-oriented research became evident in the U.S. Department of Energy’s Aquatic Species Programme (1978-1996), during which more than 3,000 strains were screened. Nitrogen deprivation was shown to increase the lipid content, although it simultaneously reduced overall productivity. Subsequent attempts at genetic engineering with ACC-ase increased expression of a key enzyme in lipid synthesis but did not result in substantially higher oil yields. The program also demonstrated that up to 90% of supplied CO₂ could be utilized for biomass production. Nevertheless, production costs remained approximately twice as high as those of petroleum and diesel.⁵

Renewed interest emerged in the early 2000s due to climate change, rising oil prices, wastewater management, and carbon mitigation. One kilogram of algal biomass can bind up to 1.8 kg of CO₂.² However, given persistent cost and technological challenges, it became evident that processes must become more robust and economically efficient.⁶ This development led to the biorefinery concept.

The biorefinery approach aims to improve economic performance by valorizing multiple biomass components. In addition to lipids for fuel production, proteins and carbohydrates can be used for animal feed, while thermochemical processes allow the production of biochar.³ High-value products such as DHA supplements, astaxanthin, and carotenoids are particularly relevant for cross-financing. However, these specialized markets are relatively small and subject to strict regulatory approval procedures, which often require five to ten years.⁷

Algal biomass can be processed via thermochemical or biochemical pathways. In thermochemical conversion, dried biomass is heated to several hundred degrees Celsius, producing bio-oil, combustible gases, and biochar. In biochemical conversion, bacteria or yeast ferment algal carbohydrates to produce biogas or bioethanol. Hydrothermal liquefaction enables wet biomass to be processed without prior drying, thereby reducing energy demand.⁴ However, nitrogen removal remains necessary, and high levels of polyunsaturated fatty acids can reduce fuel stability during storage.² Metabolic engineering, including CRISPR-Cas9 gene editing method, has achieved oil yield increase of up to 169% by redirecting energy storage from starch to lipids.⁴ In addition, transesterification enables conversion of extracted algal oil into biodiesel suitable for conventional engines.³ Figure 1 summarizes the overall production pathway for microalgal biofuels, from cultivation through downstream conversion.¹

Figure 1: Simplified production pathway of microalgal biofuels from cultivation to fuel conversion (own illustration)

Microalgae exhibit considerable biological advantages. They do not compete with food production and require only 1.1-2.5% of land to meet significant fuel demand, compared to 24% for oil palm and 800% for corn.² This is also why algae are classified as third- or fourth-generation biofuels, as they neither require arable land like corn nor a structure that is difficult to treat chemically like wood.⁴ They can grow on marginal soils and some species of algae double their biomass within a day.² Dry biomass typically contains 20–50% oil, resulting in potential yields of approximately 85,700 litres per hectare per year, compared to 6,000 litres for palm oil.² Photosynthetic efficiency ranges from 3–8%, which is six to twelve times higher than that of land plants, and their oil content may increase to 85% under stress conditions.²

Despite these technological advances and biological advantages, the large-scale deployment of microalgae bioenergy ultimately depends on its economic feasibility.

2 Economic performance

Despite considerable technological progress, the economic viability of microalgal biofuels remains a key challenge hindering large-scale commercial deployment.

High capital costs for cultivation systems, including pumps, pipes, and monitoring infrastructure, contribute significantly to overall expenditure.¹ Consequently, the industry is focusing on high-value products.¹ The carotenoid market alone has an estimated volume of USD 1.2 billion, and astaxanthin products can reach prices of approximately USD 7,150 per kilogram. Additional revenue streams include omega-3 supplements and pharmaceutical applications. However, these markets remain limited and highly sensitive to saturation. As a result, revenues from high-value products are insufficient to support large-scale fuel production, creating a structural mismatch between market volume and energy demand.⁷

Interest has also grown in integrating algae cultivation with wastewater treatment and carbon sequestration. Algae can filter nitrogen and phosphorus while incorporating CO₂ into biomass. Pilot projects in India report CO₂ absorption rates of 70–90%. Nevertheless, high production costs remain the primary barrier to competitiveness.

In 2007, conventional biofuels were produced at costs of USD 1.40-1.81 per litre, whereas algae biomass production reached approximately USD 2.80 per litre.² Although the prices for conventional diesel are higher nowadays, biodiesel from algae is not currently competitive in terms of price.

According to Davis et al. (2016), cultivation accounts for approximately USD 278 per tonne of biomass, while nutrients and CO₂ supply contribute a further USD 112 per tonne. Additional costs arise from dewatering and CO₂ compression, highlighting the dominance of infrastructure-related expenditure.⁸ Even under optimistic productivity assumptions of 26 g/m2/day, final fuel prices remain around USD 4.49 per GGE, which is significantly higher than competing biofuel feedstocks. For commercial viability, target prices of approximately USD 3 per GGE would be required.⁸

Overall, economic feasibility remains highly dependent on technological progress, stable policy support, and revenues from co-products.⁷⁸ Without substantial improvements in productivity and cost reduction, large-scale fuel production from microalgae is unlikely to become competitive in the near future.⁸

While economic performance is a critical factor determining the commercial feasibility of microalgal bioenergy, environmental sustainability is equally important. The following section therefore examines the ecological performance of microalgae bioenergy systems.

3 Ecological performance

The ecological performance of algal biofuels is most appropriately assessed using life-cycle assessment (LCA), because impacts arise across the full value chain from cultivation and harvesting to processing and fuel conversion.⁹ Review evidence shows that algae pathways can perform better or worse than fossil fuels depending on system design, electricity supply and nutrient management, so sustainability is a design-dependent outcome rather than an inherent feedstock property.¹⁰ Early LCAs stressed that energy-intensive dewatering and drying could cancel climate benefits under carbon‑intensive electricity assumptions.¹¹ More recent work shows improved performance when systems use low‑carbon electricity and circular inputs such as recycled nutrients and industrial CO₂ streams.¹² This section explains the key ecological drivers and why reported performance has shifted as designs and assumptions evolved.¹²

Energy demand is consistently identified as the dominant hotspot because microalgae are cultivated in dilute suspensions that require energy-intensive separation.¹¹ Low biomass concentrations mean large water volumes must be processed per unit biomass, so centrifugation, filtration, flocculation and thermal steps often dominate electricity use in LCAs.¹¹ When grid electricity is fossil‑intensive, upstream power-sector emissions attributed to these unit operations can drive lifecycle GHG results toward fossil-fuel levels.⁹ When electricity is low‑carbon, the same unit operations contribute fewer upstream emissions and overall GHG results improve.¹² This electricity–process interaction explains why later assessments with renewable power assumptions and improved harvesting often report better ecological performance than early studies.¹²

Nutrient and water inputs are the second major ecological determinants because algae require nitrogen, phosphorus and water, creating upstream burdens if supplied through industrial fertilizer and freshwater withdrawals.⁹ Synthetic fertilizer production contributes to energy use and emissions in many algae LCAs, and nutrient losses influence eutrophication indicators.¹¹ Integration with wastewater treatment is widely proposed because algae can assimilate dissolved nitrogen and phosphorus from wastewater while producing biomass, thereby substituting recycled nutrients for synthetic fertilizers.¹³ Water-scarcity constraints also shape feasible siting, as national-scale scenarios show that water demand can become limiting depending on climate and design choices.¹⁴ Together, these mechanisms make circular nutrient sourcing and non-freshwater options central to improving ecological performance over time.¹³

Land-use impacts are often viewed as an advantage relative to crop-based bioenergy because algae can be cultivated on non-arable land, reducing direct food competition.⁹ Spatial modelling indicates that facilities can be sited to reduce conflicts with agriculture and biodiversity if ecological constraints guide location choice.¹⁵ However, land and biodiversity advantages are conditional on siting, infrastructure footprint and avoidance of high-value habitats, so monitoring and planning remain necessary.¹⁰ These siting considerations become especially important in marine cultivation, where farms interact directly with coastal ecosystems.¹⁶

Marine macroalgae farming reduces terrestrial land pressure but introduces site-specific ecological risks that must be managed through spatial planning and monitoring.¹⁶ Seaweed farms use longlines or rope arrays in the photic zone and can influence light penetration, hydrodynamics and habitat structure; biological interactions such as disease dynamics and epiphytes are also highlighted as risk pathways.¹⁶ Monitoring evidence suggests impacts can be limited when farms are appropriately designed and sited, but outcomes depend on local conditions and therefore require adaptive management.¹⁷ In eutrophicated seas such as the Baltic Sea, cultivation is also proposed as nutrient removal because harvesting biomass exports nitrogen and phosphorus from the system.¹⁸ This illustrates how ecological performance can improve when biomass production is coupled to ecosystem-service functions, while also creating additional governance requirements that connect ecology to social acceptance.¹⁹

Environmentally sustainable algae farming therefore requires explicit design choices that reduce the dominant LCA hotspots rather than assuming algae farming is per se automatically sustainable.¹⁰ First, process designs should minimize energy intensity by prioritizing low-energy harvesting routes and by avoiding unnecessary thermal drying when wet conversion pathways are feasible, because harvesting and drying are repeatedly identified as high-impact steps.¹¹ Second, nutrient strategies should prioritize recycling—especially wastewater-derived nitrogen and phosphorus—because this substitutes industrial fertilizer inputs and links biomass production to pollution control.¹³ Third, siting and water management should reflect local hydrology and evaporative loss, since scale-up feasibility is constrained by regional water availability.¹⁴ These requirements show how “sustainable algae farming” (Figure 2) is operationalized through concrete engineering and siting rules, which also increases the credibility of sustainability claims needed for acceptance and policy support.¹⁹

Figure 2: Engineering mechanisms for environmentally sustainable algae farming (own illustration)

4 Social impact

Social acceptance is pivotal for algae bioenergy because perceived risk, benefit and fairness shape siting decisions, investment and long-term policy support.¹⁹ Stakeholder research finds algae bioenergy is often viewed as environmentally promising but technologically uncertain, which makes trust in institutions and verification of sustainability claims central to acceptance.¹⁹ This section therefore focuses on how acceptance has evolved, what benefits are perceived, and which social risks can undermine legitimacy.¹⁹

Acceptance has changed over time as bioenergy debates shifted from early optimism to more conditional support based on sustainability safeguards.¹⁹ Criticism of first-generation biofuels emphasized land-use change, biodiversity impacts and food-versus-fuel trade-offs, which reduced confidence in some crop-based pathways.¹⁹ Algae are frequently framed as a third-generation alternative because cultivation can occur on non-arable land and can be integrated with wastewater nutrient removal, addressing central concerns raised in earlier controversies.⁹¹³ However, acceptance remains conditional because stakeholders also evaluate whether these benefits are realistic at scale and whether environmental risks are visibly managed.¹⁹ This conditionality becomes sharper when costs and technology maturity are considered. Namely, that fossil fuels remain cheaper to produce than algal fuels.²⁰

Economic uncertainty is a key social barrier because high expected production costs can undermine confidence in deployment and raise questions about public spending priorities. Recent reviews identify high costs as a primary barrier to commercialization, reinforcing the perception that algae fuels require sustained support to reach competitiveness.²⁰ Social acceptance can improve when technological learning becomes tangible through demonstration plants, because visible progress changes expectations about future costs and feasibility.²¹ At the same time, biotechnology can raise perceived risks even if performance improves, which requires transparent governance to maintain trust.²²

Biotechnology is socially salient because genetic engineering can enhance lipid productivity and stress tolerance while raising biosafety and ethics concerns.²² Metabolic engineering strategies are described as routes to higher yields and improved process resilience, strengthening the technical case for algae bioenergy.²² However, concerns about unintended release and ecological interaction require containment, monitoring and regulatory oversight to maintain legitimacy, particularly for open systems.²² Governance quality therefore becomes part of the “social license to operate,” because communities evaluate whether risks are managed and whether information is shared transparently.¹⁹ This governance dimension is also evident in marine farming, where community impacts are immediate and spatially visible.

Marine macroalgae farming can generate positive social impacts through jobs, income and coastal economic diversification, but distribution depends on market structure and governance.²³ Evidence syntheses report that seaweed cultivation can provide employment in farming, harvesting and processing and can create income opportunities for coastal communities.²³ These benefits can strengthen acceptance when value chains are locally anchored and when communities perceive tangible co-benefits from projects.²³ At the same time, negative impacts can arise because coastal waters are shared spaces; farms may conflict with fisheries, tourism, conservation and transport, leading to disputes over access and aesthetics.¹⁶ Marine spatial planning and stakeholder engagement are therefore critical to reduce conflict by clarifying zones, rights and monitoring responsibilities. These social dynamics connect directly to policy design, which determines incentives, standards and the institutional capacity to manage conflict and verify sustainability claims.²⁴

5 Political and legal aspects

5.1 Key policies influencing development

Policy frameworks influence algae bioenergy by setting research support, market incentives and sustainability standards. Supportive policy is particularly important because algal biofuels remain cost-challenged relative to fossil fuels, and high production costs are repeatedly identified as a main commercialization barrier.²⁰ Energy security considerations can also elevate interest in domestic fuel options during geopolitical tension and supply disruptions.²⁴ Because algae can be cultivated in diverse regions using non-arable land, policy debates sometimes frame algae as a long-term option for regional fuel diversification.¹⁵

Public R&D is a central instrument because cost reductions and ecological improvements depend on technological learning. Techno-economic analysis indicates that gains in cultivation productivity, harvesting efficiency and conversion yields are required for commercial feasibility, motivating sustained R&D support.²¹ R&D can also target the energy and nutrient hotspots identified by LCAs, linking innovation policy directly to improved lifecycle performance.¹² This creates a pathway in which public support accelerates learning and reduces both costs and emissions, improving the credibility of sustainability claims that matter for social acceptance.¹⁹

Carbon pricing can further support algae fuels by internalizing the climate costs of fossil fuels and improving the relative economics of low-carbon alternatives.²⁵ Carbon taxes and emissions trading systems increase the effective price of fossil emissions, and higher carbon prices make fuels with lower lifecycle GHG emissions more attractive.²⁵ If algae systems reduce emissions through low-carbon electricity and circular nutrient inputs, carbon pricing strengthens incentives to adopt those designs and rewards verified performance.¹² Together, R&D support and carbon pricing illustrate how policy can couple innovation with lifecycle sustainability outcomes, providing an enabling environment for advanced algae bioenergy.

Beyond R&D and carbon pricing, policy mixes matter because algae fuels require long investment horizons and credible performance rules. Energy-security frameworks emphasize vulnerability reduction and reliability. Domestic bioenergy can therefore appear politically attractive when imported energy creates exposure to geopolitical disruption.²⁴ Carbon pricing provides an economy-wide signal, but the IPCC also discusses that complementary instruments may be needed where innovation spillovers and infrastructure lock-in limit the response to prices alone.²⁵ In practice, combining long-term R&D programs with clear lifecycle-performance requirements can reduce investor uncertainty and steer technology development toward verified emissions reductions rather than volume-only expansion.

5.2 Alternative policy approaches

The development and deployment of microalgal bioenergy is not solely determined by technological progress and economic performance; it is also strongly influenced by political frameworks and regulatory instruments. An overview of the main policy approaches discussed in this section is provided in Figure 3.

Figure 3: Key policy instruments influencing the deployment of microalgal bioenergy (own illustration)

Carbon pricing internalises the external costs of greenhouse gas emissions, aiming to make low-carbon technologies economically competitive. Carbon Capture and Utilisation (CCU) complements and, in certain contexts, challenges the traditional, rigid, volume-oriented approach to carbon capture and storage (CCS), thereby internalising the external costs of greenhouse gas emissions. CCU aims to make low-carbon technologies economically competitive. Therefore, CCU with algae represents a policy-relevant alternative to classical CCS by transforming CO₂ into a marketable product. One advantage of this is that algal CCU achieves a net efficiency of 73%, compared to 48% for conventional CCS. Furthermore, CCU avoids 4.05 tonnes of CO₂ equivalents per tonne of methanol. It also becomes more economically attractive and highly profitable for algae production when the carbon tax reaches USD 100 per tonne. However, the capital expenditure is enormous, with construction costs of nearly USD 1 billion being almost seven times higher than classic MEA (monoethanolamine) concepts. This is particularly relevant given that these reactors must be replaced every five years, and they require 1,000 hectares of land. Therefore, carbon pricing alone does not automatically ensure market diffusion, as structural cost disadvantages and capital intensity remain significant barriers.²⁶

Another approach is wastewater integration and environmental regulation, whereby wastewater regulations create pressure to reduce nutrient discharge and greenhouse gas emissions simultaneously. Microalgae systems are therefore positioned as integrated solutions, combining water treatment and bioenergy production. Algae can support the removal of nitrogen and phosphorus from wastewater, and one gram of algal biomass binds up to 1.83 grams of CO₂. Furthermore, the oil yield per area is 200 times higher than that of conventional crops such as corn. However, critics often point out that raceway ponds are limited to a depth of 20–30 cm due to light constraints; otherwise, the water mixed with algae would become too dark, preventing the lower algae from receiving enough light. Harvesting is also quite expensive, accounting for 20–30% of operating costs. Furthermore, there are high contamination risks and regulatory complexity, which limits large-scale commercial deployment.²⁷

The Sustainable Aviation Fuel (SAF) Mandates aim to create guaranteed demand for low-carbon aviation fuels through blending mandates. Therefore, regulatory intervention is required, as airlines will not switch voluntarily due to the high costs involved. However, an advantage of the SAF approach is that blending quotas provide legal certainty, and investment incentives are offered via multipliers and financial support. One example of this is RED II, which states that 1 litre of sustainable aviation fuel counts towards climate targets as much as 1.2 litres of conventional biofuel. Direct financial support also exists in the form of subsidies, grants, and contracts for difference (CFDs), whereby the state guarantees producers a fixed purchase price for many years. If the market price falls below this price, the state pays the difference. However, a significant drawback is that SAF is 2–6 times more expensive than fossil kerosene, and there is a risk of indirect land use change (ILUC) and diversion of feedstocks. This ‘theft from the road’ does not lead to new plant construction, but rather to refineries processing used fat into jet fuel instead of green diesel. Furthermore, the supply of advanced SAF fuels is limited, with a maximum capacity that would cover only about 5.5% of projected kerosene demand in the EU.²⁸ In contrast to sector-specific blending mandates in aviation, the Low Carbon Fuel Standards (LCFS) shifts the focus of regulation from fixed volumes to lifecycle carbon intensity targets, with credits generated based on CO₂ reduction performance. This technology-neutral framework therefore rewards low-carbon intensity fuels. This creates market-based flexibility through traceable credits. Conversely, these standards favour established fuels, such as corn ethanol and hydroprocessed esters and fatty acids (HEFA). Furthermore, credit price volatility creates uncertainty in the market, and there is a structural mismatch between the planned capacity and the domestic waste oil supply.²⁹

Another approach is R&D and demonstration funding, where public funding aims to reduce technological risk in the early stages and enable commercial scaling. These government programmes address the gap between pilot projects and market deployment. An initial public investment of USD 69 million is available, providing access to ATP3 test beds, which reduce capital expenditure and mitigate technological risk. However, it should be noted that large-scale facilities in the next stage require around USD 150 million, and this illustrates that public R&D funding can reduce early-stage technological risk but does not eliminate the structural financing gap between pilot and commercial scale.³⁰

In conclusion, political and legal frameworks are indispensable for the development of microalgal bioenergy; however their effectiveness ultimately depends on consistent long-term policy signals and the ability to overcome structural cost disadvantages.

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1
Borowitzka, M. A. Commercial production of microalgae: ponds, tanks, tubes and fermenters. Journal of Biotechnology 70, 313–321; 10.1016/S0168-1656(99)00083-8 (1999).
2
Chisti, Y. Biodiesel from microalgae. Biotechnology advances 25, 294–306; 10.1016/j.biotechadv.2007.02.001 (2007).
3
Brennan & Owende (2010); 10.1016/j.rser.2009.10.009.
4
Raheem, A., Prinsen, P., Vuppaladadiyam, A. K., Zhao, M. & Luque, R. A review on sustainable microalgae based biofuel and bioenergy production: Recent developments. Journal of Cleaner Production 181, 42–59; 10.1016/j.jclepro.2018.01.125 (2018).
5
Sheehan, J., Dunahay, T., Benemann, J. & Roessler, P. Look Back at the U.S. Department of Energy’s Aquatic Species Program: Biodiesel from Algae; Close-Out Report, 1998.
6
Shuba, E. S. & Kifle, D. Microalgae to biofuels: ‘Promising’ alternative and renewable energy, review. Renewable and Sustainable Energy Reviews 81, 743–755; 10.1016/j.rser.2017.08.042 (2018).
7
Borowitzka, M. A. High-value products from microalgae—their development and commercialization. J Appl Phycol 25, 743–756; 10.1007/s10811-013-9983-9 (2013).
8
Davis, R. et al. Process Design and Economics for the Production of Algal Biomass: Algal Biomass Production in Open Pond Systems and Processing Through Dewatering for Downstream Conversion, 2016.
9
Clarens, A. F., Resurreccion, E. P., White, M. A. & Colosi, L. M. Environmental life cycle comparison of algae to other bioenergy feedstocks. Environmental science & technology 44, 1813–1819; 10.1021/es902838n (2010).
10
Chamkalani, A., Zendehboudi, S., Rezaei, N. & Hawboldt, K. A critical review on life cycle analysis of algae biodiesel: current challenges and future prospects. Renewable and Sustainable Energy Reviews 134, 110143; 10.1016/j.rser.2020.110143 (2020).
11
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