Sustainable Development Introduction

In 2015, world leaders defined the 17 Sustainable Development Goals (SDGs) for the 2030 Agenda for Sustainable Development. As we approach the 2030 deadline, progress towards these goals remains insufficient. The recent 2025 United Nations Sustainable Development Report highlights concerning trends regarding the lack of progress made towards achieving the goals.

Our device, the Cysteinator, and its implications are closely aligned with SDG 6: Clean Water and Sanitation, SDG 7: Affordable and Clean Energy, and SDG 13: Climate Action. By making use of typically disregarded waste streams and optimizing renewable energy production, the Cysteinator plays a significant role in achieving the development goals outlined by the United Nations.

Beyond SDGs 6, 7 and 13, we found that our device had connections to SDG 3: Quality Health and Well-being, SDG 9: Industry, Innovation and Infrastructure, and SDG 12: Sustainable Consumption, and many more.

Working to share this knowledge, we pursued multiple streams of outreach targeting the primary SDGs 6, 7, and 13. We engaged with our community by publishing a piece on local wastewater management in our university’s daily newspaper. By performing a Life Cycle Analysis on our device and discussing its implications with policy makers, we connected our work to future steps of production and implementation.

SDG 6: Clean Water and Sanitation

Overview

SDG 6: “Ensure availability and sustainable management of water and sanitation for all.”

SDG 6.3: Improve water quality by increasing water recycling and reuse, leaving no wastewater untreated, and reducing pollution, and hazardous discharge.

SDG 6.4: Increase water-use efficiency, ensure sustainable freshwater withdrawals, and substantially reduce the number of people suffering from water scarcity.

SDG 6.a: Expand international cooperation and capacity-building for water efficiency, wastewater treatment, and recycling and reuse technologies in developing nations.

The Cysteinator can boost the efficiency and productivity of dark fermentation (DF) systems, which are anaerobic processes that produce biohydrogen from biowaste. These systems can use almost any organic waste, including food waste, municipal waste, sewage sludge, and agricultural and crop residues [1][2][3]. By increasing hydrogen yields, our device enhances both energy recovery and wastewater (WW) treatment capacity through the supplementation of the amino acid L-cysteine in DF media, improving water management and creating a scalable solution that supports SDG 6.

SDG 6.3a: Promoting Water Sanitation Efforts

Municipal water and wastewater (MWW) treatment accounts for more than one-third of the energy used by the United States government and 3-4% of energy use nationwide [4]. However, it could be harnessed to generate at least twice the amount of energy it consumes, immense untapped potential that DF systems can unlock to reduce the net energy demand of MWW treatment [5]. DF systems can bridge this gap by utilizing MWW. By increasing hydrogen production yields, the Cysteinator enables efficient water recycling and reuse as called for by the first part of SDG 6.3 (6.3a).

Stakeholder Feedback: Professor Cresten Mansfeldt

Professor Mansfeldt, a professor of Environmental Engineering at the University of Colorado Boulder, encouraged us to consider the enormous potential of WW streams. He explained that WW treatment facilities are increasingly viewed more as “water resource recovery stations” that prioritize energy recapture, and that biowaste must be recognized as a resource rather than a liability. This perspective shift is essential for communities in regions without access to similarly well-distributed resources that could expand the diversity of their sustainable energy portfolios; waste is everywhere, while traditional fossil fuels are not. Our discussion with Professor Mansfeldt contextualized the Cysteinator’s application to valuable resource-recovery technologies and expanded our understanding of the true potential impact of the Cysteinator.

Stakeholder Feedback: Dr. Michelle Halsted & Shakeel Balroop

Dr. Michelle Halsted, an engineer with Noblis, and Shakeel Balroop, a consultant with the Solid Waste Association of North America (SWANA), encouraged us to consider how the Cysteinator could thrive as a technology by taking strategic advantage of waste streams, municipal and industrial. They recommended we couple the Cysteinator with strategic industrial waste streams since our device operates more efficiently with a sulfur source, and they noted that construction demolition projects and egg-waste facilities like such as chicken hatcheries and bakeries tend to have high concentrations of sulfur in their WW, which are potential resources for our device’s applications. A strong rate of return on investment further incentivizes adoption, positioning our device as not only WW treatment but also as an alternative municipal revenue stream. In their experience, waste management facilities are more receptive to integrating innovations into their treatment processes when expenses are low. They emphasized that our device is best framed as an economical solution to an expensive problem.

Connection to SDG 12: Responsible Consumption & Production

Resource recovery is an important part of SDG 12: Responsible Consumption and Production. Under SDG 12.2, nations are called to use resources efficiently, which can be combined with SDG 12.4, emphasizing safe and sustainable waste management throughout waste life cycles. Waste contains numerous precursors that should not be discarded but rather recycled, reused, and transformed into valuable products. When managed this way, waste streams can provide the raw materials for energy and other industry applications, reducing the need for additional resource extraction and lowering negative environmental impact. However, effective implementation is crucial, as improper management may lead to negative impacts such as pollution from poorly designed processes and the risk of prioritizing waste-to-energy over reducing total waste and increasing efficient consumption. By utilizing these waste streams in DF systems, the Cysteinator supports the positive impacts of SDG 12 by reducing fossil fuel reliance, cutting greenhouse gas emissions, and creating new economic opportunities in waste management.

SDG 12.5, which emphasizes reducing waste generation through prevention, recycling, and reuse, overlaps significantly with SDG 6.3. Proper utilization of food waste, whose mismanagement accounts for about 8% of global GHG emissions, both reduce emissions and generate enough energy to power nearly one million American homes each year [6]. Approximately 25% of sewage sludge still goes to Municipal Solid Waste (MSW) landfills unused, while only 14% is incinerated for energy recovery, a process which itself emits GHGs [7]. As a recycling method, DF systems can process diverse waste streams such as Municipal Wastewater (MWW), MSW, and sewage sludge for biohydrogen production, making these streams an efficient and effective Waste-to-Energy (WTE) pathway that directly supports SDG 12.5.

SDG 6.3b: Expanding Wastewater Treatment Access

Internationally, the question of untapped energy generation from wastewater (WW) comes secondary to the pressing need to treat WW more effectively. As global populations continue to rise, so will the WW generated. An estimated 113 billion m³ of household wastewater, or 42% of the total generated, was discharged without safe treatment in 2022 [8]. Although our device cannot directly address the 45% of untreated WW from households without sewage or septic connections, it can target 20% of untreated WW from sewer flows that receive only primary treatment or bypass discharge standards [9]. The Cysteinator creates an economic incentive to upgrade primary treatment facilities to WTE streams, encouraging municipalities to improve sewage infrastructure.

By 2030, the health and livelihoods of 4.8 billion people will be at risk without improvement of existing water quality monitoring infrastructure [10]. Lack of access to clean water is associated with mass dehydration, improper sanitation, and crippled crop supply, all of which can cause economic decline, and widespread water-borne diseases such as cholera, typhoid fever and rotavirus [11]. The Cysteinator expanding WW treatment access, as called for by SDG 6.3b, ensures DF systems operate effectively, advancing both public health and sustainable hydrogen production.

Stakeholder feedback: Professor Sovik Das

Professor Das emphasized that WTE technologies are gaining interest globally because of their WW treatment potential. In India, progress has been made in improving waste disposal, but sludge management remains a significant challenge and poses a public health risk. In some regions of India, less than 5% of wastewater is treated before being discharged, compared with over 70% in high-income countries [12][13].

By integrating our device into DF systems, the treatment of WW can become more efficient, scalable, and economically viable. The Cysteinator increases hydrogen yields, which makes DF production cost-effective and creates stronger economic incentives to invest in sludge treatment infrastructure. This advances SDG 6.3 by encouraging the widespread adoption of WW treatment, leading to reduced pollution, improved sanitation, and safer water management in both developing and developed nations.

Connection to SDG 3.9

This is directly related to SDG 3.9, which focuses on “[reducing] the number of deaths and illnesses from hazardous chemicals and air, water, and soil pollution and contamination.” By contributing to better wastewater treatment, our device can limit the spread of water-borne diseases, which kill nearly 800 children under the age of 5, every single day [14].

SDG 6.4: Ensuring Sustainable Water Use

SDG 6.4 calls for the reduction of worldwide water scarcity. Currently, 2.4 billion people live in water-stressed countries, many of which are attempting to tackle water scarcity by expanding desalination plants that combust fossil fuels to remove salt from seawater [15]. Unfortunately, the rise of desalination adversely affects both our atmosphere and the ocean ecosystems we must protect. Hydrogen production via electrolysis, the leading method, is extremely water consumptive. While electrolysis is carbon-free, overlooking the water input demand for energy generation is comparable to disregarding the environmental cost of GHG emissions. In contrast, DF systems, made more viable by the Cysteinator, can produce clean hydrogen while returning over 20 gallons of clean water per kg of H₂ produced, offering a sustainable alternative that reduces water stress [16].

Connection to SDG 14: Sustainable Marine Resource Use

SDG 14 advocates for the conservation and sustainable use of our oceans, seas, and marine resources. Aquatic species like fish and crabs are killed by desalination plant intake screens, while smaller organisms, including billions of plankton, fish larvae, and eggs, pass through screens to the facility, where they die [17][18]. Desalination also produces highly concentrated brine, denser and saltier than natural seawater, that is discharged back into the sea [19]. This brine tends to sink to the seafloor, creating localized zones of high salinity and contaminating ecosystems with residual chemicals that threaten marine life [20]. To achieve SDG 14, we cannot rely on energy generation methods that depend on desalinating our oceans to produce freshwater. This has significant impacts on SDG 6.4, as it reinforces why we must move away from methods like electrolysis, given the significant environmental damage caused by desalination.

Stakeholder Feedback: Professor Lisa Colosi-Peterson

Professor Colosi-Peterson emphasized the critical importance of understanding the necessary tradeoffs between water and energy. Depending on which is in abundance, different regions will have different resource allocation priorities. She emphasized that given their resource constraints, it makes sense for a country like Saudi Arabia, which is oil-rich but freshwater-poor, to combust fossil fuels for desalination at great environmental cost. This conversation helped us recognize that alternative energy sources must consider all inputs, and not all communities can afford or have access to the same inputs.

In nations like Saudi Arabia, where water scarcity is severe, electrolysis is not a viable pathway for large-scale hydrogen production, despite the region’s strong solar potential. Even if renewables are deployed at this scale, as in the United States west coast where grid oversupply can redirect electricity to electrolysis, the Middle East and North Africa lack the spare water needed for splitting water. In contrast, DF systems, aided by the Cysteinator, increase hydrogen production while recycling MWW, offering a sustainable alternative with the potential to advance global water efficiency and reuse. Our conversation with Professor Colosi-Peterson highlighted that enhancing DF has motivations beyond hydrogen production, further contributing to SDG 6.4.

Connection to SDG 9.4: Sustainably Upgrade Industries and Infrastructure

SDG 9.4 focuses on the need to make modernized industries sustainable, increasing resource-use efficiency, and enabling the adoption of cleaner and environmentally sound industrial processes. The need to transition from current methods of hydrogen production is rooted in the push to pursue sustainable industrialization.

SDG 9.4 focuses on the need to make modernized industries sustainable, increasing resource-use efficiency, and enabling the adoption of cleaner and environmentally sound industrial processes. The Cysteinator increases resource-use efficiency by maximizing the energy recovery from organic wastes, while also furthering the transition away from the current energy and carbon intensive H₂ production methods.

Engaging with our local community: WTE at Rivanna Authority

To further evaluate the Cysteinator’s impact, we engaged with Rivanna Water & Sewer Authority, our local wastewater treatment facility. We talked to Brian Haney, the facility’s WW manager, about the future of integrating WTE streams into their Advance Water Resource Recovery Facilities. He informed us that in recent years his facility has been collecting biogas produced during the treatment process to produce energy. They recycle that energy to power future WW treatment, and when in excess they sell the energy back to the grid. This demonstrates that technology analogous to the Cysteinator has demand and precedence for implementation in local WW treatment facilities.

SDG 7: Affordable and Clean Energy

Overview

SDG 7: “ensure access to affordable, reliable, sustainable, and modern energy for all”

SDG 7.2: substantially increase the share of renewable energy in the global energy mix.

SDG 7.3: double the global rate of improvement in energy efficiency, or the use of less energy to produce the same amount of economic output, service, or product.

Designed to supplement dark fermentative bacteria, the Cysteinator enables the generation of sustainable biohydrogen to effectively compete with fossil fuel-based energy. Our engineered Escherichia coli is a device designed to produce exactly enough L-cysteine to prime dark fermentation feedstocks. By increasing the DF capacity to produce biohydrogen, the Cysteinator will ultimately increase access to reliable, efficient, sustainable, modern energy for all, as called for by SDG 7.

SDG 7.3: Improving Energy Efficiency

In the United States (U.S.), electricity consumption is projected to nearly triple by 2050 [21]. The nation does not have the ability to meet this unprecedented demand. Reporting by major U.S. grid operators indicates that capacity shortages will occur as early as 2026, while we have just about four years before the assets that power our grid completely expire [22]. If this trend is not reversed, the risk of blackouts will be 100x by 2030, leading to lowered quality of life and economic stagnation [23]. The national failure to support grid load growth sits in the broader context of the need to increase global energy efficiency. Shifting away from the U.S., the scale of the global problem is much greater. Investment in the global grid infrastructure that ensures international energy security is not keeping pace with the expansion of electricity generation, because many developing economies have struggled to mobilize enough capital for energy infrastructure [24]. This has exacerbated regional disparities in energy security and transition. For example, even though it is 20% of the global population, Africa has attracted just 2% of clean energy investments, and even that vanishingly small share is continuing to fall [25]. This means that for some nations – developing ones in particular – increasing energy supply alone is not sufficient: increasing energy efficiency in accordance with SDG 7.3 is key to meeting energy demand.

We need to execute an all-hands-on-deck strategy to meet electricity demands immediately. This means that we not only increase energy supply but also increase energy efficiency, as recognized by 7.3.

Cysteinator-enhanced Dark Fermentation Biohydrogen Production Furthers SDG 7.3

H₂ is more thermodynamically favorable, as it is almost three times more energy dense than traditional fossil fuels [26].

This large difference in energy density means that less H₂ needs to be burned to generate the same energy, enabling more efficient energy generation. Additionally, the Cysteinator can support the energy-efficient DF-MEC system. The MEC, which uses just about 10% the amount of electricity (3.3 kWh/kg H₂³) that the leading alternative method of green hydrogen production requires (electrolysis: 40-55 kWh/kg H₂³) to make the same amount of hydrogen, is the prime technology to deploy for storing electricity not immediately used in the form of hydrogen [27]. The MEC is decidedly more energy efficient: the obvious choice for progress on SDG 7.3. Although widespread H₂ production through dark fermentation currently suffers from high production costs, the Cysteinator makes a direct contribution to increasing energy efficiency in the context of enabling sustainable, higher yield biohydrogen production.

Connection to SDG 8: Productive Employment and Decent Work for All

We recognize the potential challenges that widespread implementation of biohydrogen may pose in the context of SDG 8, which emphasizes sustainable economic growth and decent work for all [28]. SDG 8.3 promotes policies that support job creation, and we acknowledge that the transition away from fossil fuels will require communities and their governments to undertake careful planning for the maintenance of a stable job market [29]. In mining regions with coal-dependent economies, communities must be supported by reskilling and workforce development to maintain economic stability throughout the sustainable energy transition. Likewise, in oil-rich areas like Alaska, where a significant share of GDP is linked to fossil fuel production, an abrupt or poorly executed shift to biohydrogen could lead to job losses and even population decline [30]. As we consider SDG 7, we also understand the importance of considering the full breadth of socioeconomic impacts and promoting a transition that balances environmental sustainability with long-term economic well-being for all.

Stakeholder Feedback: Professor Andres Clarens

Prof. Clarens, Professor in the Department of Civil and Environmental Engineering at the University of Virginia and Associate Director of the UVA Environmental Institute, made us aware that Li-ion batteries are promising alternatives and the leader in short-term (one-to-four hour) energy storage. But this is exactly the problem: few alternatives exist for the long-term storage necessary to get wind and solar power from one part of the country to another or to store power over an entire season of the year. H₂ is the most viable solution to achieve higher efficiency energy storage, and according to the National Renewable Energy Laboratory, hydrogen long-term storage could become cost-effective in the near future; this is essential because, as he emphasized, increasing energy efficiency and so furthering SDG 7.3 can only go hand in hand with increasing the economic efficiency of technologies proposed to target it. Feedback from Prof. Clarens helped us better understand that economically efficient hydrogen may first come as a form of long-term energy storage, not just as a direct fuel source, which has expanded our consideration of the applications and impacts of our device.

Connection to SDG 6: Availability and Sustainable Management of Water

Pumped-storage hydro stations currently represent 95% of U.S. grid storage,10 but continued reliance on such systems threatens our commitment to SDG 6, especially SDG 6.4, the call to increase water-use efficiency – and SDG 6.6, the call to protect and restore water-related ecosystems, including the rivers and lakes that are profoundly affected by engineering interventions to make use of their water reservoirs. Shifting to more efficient H₂ based forms of energy storage allows for decreased reliance on hydro stations, contributing to achieving the tenets of SDG 6.

SDG 7.2: Increasing Share of Renewable Energy

SDG 7.2 calls for increasing the share of renewable energy in the global energy mix. The combustion of fossil fuels releases carbon dioxide (CO₂) and other greenhouse gases (GHGs) into the atmosphere. Historical cumulative net CO₂ emissions from 1850 to 2019 were 2.4 trillion metric tons of CO₂, of which 42% occurred between 1990 and 2019, when we reached the most average annual GHG emissions of any decade so far on record [31].

This unprecedented pollution has caused higher atmospheric CO₂ concentrations than at any other time in at least 2 million years, and warmed global surface temperature by 1.1 °C since the Industrial Revolution; the five hottest years ever recorded have occurred since 2015 [32]. As a result, sea levels have risen, previously "extreme" weather events have become more frequent, species & whole local ecosystems have been lost to history, and our own key infrastructure, food & water security, and physical & mental health have all been profoundly impacted by these climate changes [33].

Supporting DF’s biohydrogen production furthers SDG 7.2

Renewable electrification driven by wind and solar power represents 92% of new global power capacity [34]. Wind and solar power are likely to lead to most decarbonization efforts and most major SDG 7.2 achievements. However, SDG 7.2 is not a call to increase the share of renewable electricity but renewable energy. Electricity is simply a form of energy, and focusing on only electricity will prove to be insufficient to deal with future energy demands. Current limits on intermittent wind and solar can only be overcome through means other than electricity itself, and hydrogen fuel can compensate for the insufficient capacity of electrical grids by storing what currently goes to waste. Unless reliable energy storage solutions scale up, too, the risk of blackouts skyrockets with our increasing dependence on wind and solar power [35]. In California alone, wind and solar power generated 3.4 million MWh more electricity in 2024 than the state’s main provider (CAISO) could store, up 29% from 2023; in other words, enough electricity to power every home in San Francisco for more than a year could not be captured for use [36]. Hydrogen is the perfect platform to store energy that cannot be handled by electrical grids. While we hope that hydrogen-based energy can make its way into the global energy share in the future, we recognize that in the short term that hydrogen is well-suited to elevate the efficiency of wind and solar power generation. We believe that letting environmentally friendly energy go to waste only serves as a potential argument for their impracticality by fossil fuel advocates. The Cysteinator promotes the generation of green hydrogen capable of storing the excess energy from wind and solar, devitalizing arguments against renewable energy.

Connection to SDG 3.9: Reducing Pollution Related Health Effects

The need to develop renewable and clean energy sources is directly related to SDG 3.9, which prioritizes the reduction of deaths and illnesses caused by hazardous environmental conditions. Each year, over 4 million people die from illnesses linked to air pollution [37]. Still, millions more live with them; in regions where coal is the dominant energy source or population-dense ports where coal is shipped, for example, residents suffer from poor air quality that causes numerous throat and skin ailments [38]. Additionally, entire local streams have turned brown due to contamination from nearby coal mines, highlighting the environmental and public health costs of nonrenewable energy. By enabling biohydrogen to become both a truly viable clean and renewable energy alternative and platform for storing other forms of renewable energy, our device contributes to the reduction of pollutants responsible for widespread health issues.

Stakeholder Feedback: Professor Michael Lenox

We spoke with Prof. Lenox, Tayloe Murphy Professor of Business at the University of Virginia’s Darden School of Business, to discuss the role of hydrogen in a green energy future. We learned from Prof. Lenox that the uneven geographical distribution of energy generation and use make the improvement of biohydrogen production methods ever more pressing. Most American opportunities to continue to scale wind and solar are in the (windy, sunny, and flat) geographic center of the U.S., but most of the electricity and energy demands are on the coasts. He told us that improving DF systems that produce biohydrogen contribute to the effective storage and transport of heartland wind and solar power to the biggest coastline consumers of that power would be a valuable undertaking in order to achieve SDG 7. This feedback from Prof. Lenox was crucial in helping us understand the use of biohydrogen in a green energy future. We had spent a lot of time thinking of hydrogen energy only as a source of energy, rather than a way for storing other forms of clean energy. With this feedback we were better able to understand how biohydrogen can both be used as a source of clean energy, while also increasing the practicality of other renewable energy sources such as wind and solar.

As a means of storing and transporting energy rather than an energy source itself, then, hydrogen generated through the DF-MEC system has the unmatched potential not only to store this surplus wind and solar power but to decarbonize long-distance transport and replace the fossil fuels that heavy-duty industries rely on for very high heat [38]. Hydrogen is an undeniably sustainable energy source, made renewable by sourcing it from biological WTE DF systems. By increasing the efficiency of DF systems that produce biohydrogen, the Cysteinator enables us to increase the share of biohydrogen in the global energy mix, which explicitly contributes to the achievement of SDG 7.2.

SDG 13: Climate Action

Overview

SDG 13 focuses on the urgent need to take action to combat climate change and its various impacts. As the use of our device in the broadest possible sense is precisely contributing to sustainable development by mitigating factors that threaten further climate change, we wanted to understand how our device contributes to specific subgoals.

SDG 13.2: “integrate climate change measures into national policies, strategies, and planning;”

SDG 13.3: improve education and raise awareness about the necessity of climate change mitigation, adaptation, impact reduction, and early warning, and increase human and institutional capacities to address these needs.

To address SDG 13.2, we first conducted extensive research on regional, national, and international climate policy. We demonstrated through a Life Cycle Assessment (LCA) that the Cysteinator addresses critical climate policy goals. In addition, we made recommendations for the hydrogen policy of the future. Furthering SDG 13.3, collaborated with VIT Vellore on a public outreach series on Instagram to raise awareness about the opportunities to advance SDGs with synthetic biology. .

SDG 13.2: Integrating climate change measures into policy

SDG 13.2 emphasizes the need to advance climate action through effective local, national, and international policy. Experts illuminated how economic, energy, agriculture, and infrastructure policies can be aligned with efforts to reduce emissions and increase accountability.

Stakeholder Feedback: Professor William Shobe

Professor Shobe, Director Emeritus of the Center for Economic & Policy Studies at UVA, explained how the Regional Greenhouse Gas Initiative (RGGI) serves as an example of how economic interests can align with climate action. In the years 2015-2017, RGGI led to $1.4 billion of net positive economic activity [39]. He emphasized that climate policy does not have to be at the cost of jobs and quality of life, and if designed meaningfully will stimulate job creation and higher quality of life. Our conversation with Professor Shobe encouraged us to advocate for climate policy that advances WTE technologies like the Cysteinator.

Stakeholder Feedback: Professor Lisa Colosi-Peterson

Professor Colosi-Peterson, a professor of Civil and Environmental Engineering at the University of Virginia, helped us understand why the 2020 Virginia Clean Economy Act (VCEA) was successful. By integrating Virginia’s economic goals with its sustainability agenda, the VCEA has reduced carbon emissions by 22% over the first three years of its implementation and $118.5 billion in fuel costs over the lifespan of clean energy investments [40].

Professor Shobe and Professor Colosi-Peterson deployed their economic expertise to effectively integrate climate action into policy, resulting attributable contributions to combating climate challenges. Under the advisement of Professor Colosi-Peterson we adapted the work citation, to construct a life-cycle assessment (LCA) and techno-economic analysis (TEA) to assess how the Cysteinator aligns with economic pressures.

Life-Cycle Assessment