From India to Kenya and Guatemala, the innovation is diverse. In Mumbai, a network of community toilets is saving women 150 hours a year, while a Bengaluru-based sanitation enterprise treats sewage through decentralised, off-grid systems using naturally occurring bacteria instead of power-intensive infrastructure. In Kenya, a sanitation company is turning waste into insect protein for animal feed, while in Guatemala, rainwater harvesting systems are bringing safely managed drinking water directly to homes beyond the reach of municipal networks. None of this is a pilot: it is a functioning, revenue-generating market that is only just registering in the global climate conversation. That is the paradox of the Sanitation Economy: one of the most cost-effective levers for cutting emissions and building resilience is only now being recognised as a valid climate strategy in its own right.
The sector sits at the intersection of the century’s biggest challenges: cutting emissions, strengthening water security and building resilience to extreme weather. A sector that today costs the public purse roughly $200 per person could, reimagined circularly, generate net positive value of $10 per head instead (TBC, 2019), turning a fiscal drain into a fiscal return. Globally, biogas derived from waste — wastewater, municipal and agricultural residues — already represents an estimated $28.5bn of that market (DataIntelo, 2026). Numbers like these remain a footnote in the global climate conversation, tucked into WASH reports that development economists read and climate financiers do not.
The Blind Spot
Start with the emissions. According to data from Sanitation and Water for All (2025), wastewater treatment and discharge cause 11.8% of global methane emissions and 4.2% of nitrous-oxide emissions — both far more potent than CO2 short-term. Data from the Stockholm Environment Institute (2024) show sanitation systems account for about 1.3% of global greenhouse-gas emissions overall, comparable to aviation, which gets vastly more climate-policy attention. Yet only 2% of updated Nationally Determined Contribution (NDC) activities address climate action within sanitation, and fewer than half of the 121 countries surveyed by UN-Water (2021) even mention climate risk in their sanitation policies.
The upshot is a mitigation opportunity left on the table: urine-diverting and composting technologies alone could avoid up to 336 megatonnes of CO2-equivalent emissions a year — roughly what a mid-sized industrial economy emits annually (Ravi, 2024). Renewable energy took decades to move from niche to mainstream; sanitation has not yet had its moment of reclassification, even though the technology and business models are already proven. ECOSTP’s decentralised treatment systems in India are a case in point, demonstrating how sewage can be treated with significantly lower energy and infrastructure requirements while reducing emissions.
The Systemic Pressure
Climate change, at bottom, is a water crisis wearing other people’s clothes. By 2030, global water demand is expected to outstrip supply by 40%, and by 2050, up to 5.7bn people will face water scarcity for at least a month each year. Sanitation sits where these pressures collide: untreated waste contaminates the shrinking freshwater supply, while heavier, more frequent floods overwhelm sewers built for a gentler climate. The resulting losses already run to roughly 1.5% of GDP in developing countries — about $260bn a year (SWA, 2024).
This is not simply a rural or a poor-country problem. Rapid urbanisation means more people than ever live in dense, low-lying settlements where a single storm can turn a sanitation failure into a public-health emergency, and informal settlements built on floodplains bear the brunt first. Climate adaptation plans that focus on sea walls while ignoring sewage build resilience with one hand and undermine it with the other. In Guatemala, Pluvia‘s rainwater harvesting systems show what closing that gap looks like: safely managed drinking water at home for thousands who would otherwise wait years for a municipal connection. Sanitation is not adjacent to the water-energy-food nexus; it is the plumbing running through the middle of it.
Solutions at Scale
None of this is hypothetical: a wave of SMEs is already proving that circular sanitation works commercially, not just environmentally, turning a municipal liability into energy, fertiliser, clean water and jobs in places formal utilities have never reached.
Suvidha set out to solve a specific problem: women in Mumbai’s low-income neighbourhoods losing hours daily to unsafe or inaccessible toilets. The model is proven — its community toilet centres save users 25 minutes a day, 150 hours a year for the women who rely on them most, and return 15.15 rupees per rupee invested.
ECOSTP’s problem was decentralised sewage treatment without the power, chemicals or heavy infrastructure most utilities depend on: its patented, biomimicry-based technology treats wastewater using naturally occurring bacteria alone, recycling nearly 10,000 cubic metres daily for 75,000 people and cutting more than 8,600 tonnes of CO2. iWhat’s next is capital: through the Accelerator, ECOSTP built staged growth plans for scenarios with and without outside investment, sharpening the sales and investor materials it needs to scale.
In Kenya, Sanergy set out to solve urban sanitation and waste disposal together. It is proven at city scale: 2,250 toilets serve 90,000 residents a day, with the waste collected and converted into organic fertiliser and insect protein for animal feed, turning a public-health liability into two revenue streams.
The model also diversifies by geography as fast as by technology. Guatemala’s Pluvia tackles the water crisis’s demand side directly: its rainwater harvesting systems reach more than 9,000 people a day, with 3,500 gaining safely managed drinking water at home and a further 1,500 through shared facilities, independent of municipal systems that may not arrive for years.iii Through the Accelerator, Pluvia also strengthened its financial forecasting and investor reporting, sharpening its ability to engage capital as it scales. Together, Suvidha, ECOSTP, Sanergy and Pluvia illustrate the range of the Sanitation Economy: not one technology but a toolkit, adaptable from a Mumbai high-rise to a Guatemalan village.
The scale of the prize reflects that diversity. The Toilet Board Coalition estimates the Sanitation Economy could be worth $493.9bn in Asia, $76.8bn in sub-Saharan Africa and $19.4bn in Latin America by 2030 (Toilet Board Coalition, 2025) — markets large enough to interest mainstream investors, if only the sector were classified in a way that let them look. Globally, the return on sanitation investment averages $4.30 for every dollar spent (United Nations, 2014).
The Financing Gap
Why hasn’t green capital followed? Largely because sanitation rarely appears in the taxonomies defining a “green” or “climate” investment. Reaching universal access by 2030 will cost $116bn–$229bn a year (SWA, 2025) yet between 2000 and 2018, rural and community-scale sanitation received only a tenth of total water-related climate finance (SWA, 2024) — the rest went to large infrastructure, rarely reaching the informal settlements and secondary cities where these SMEs actually operate.
Sanitation is still funded largely through traditional WASH grants, a category that has historically attracted far less aid than health or education and often sits within different funding structures and institutions from climate finance. As a result, sanitation businesses can find themselves competing within relatively constrained WASH and development funding pools, even when their models generate wider economic, social and environmental value. This includes reducing emissions, recovering valuable resources, strengthening water security and building resilience to climate impacts.
In India alone, inadequate sanitation costs the economy an estimated $53.8bn a year, or 6.4% of GDP (World Bank, 2006), yet investment in the sector continues to fall short of the scale of the opportunity. The challenge is not simply one of access to climate finance, but of how sanitation is recognised and valued within existing financing frameworks. Technologies such as biogas and resource recovery are already recognised as investable opportunities across sectors such as agriculture and waste management. Yet when these same principles are applied within sanitation, their potential to generate economic and environmental value can remain overlooked.
The Way Forward
Turning this systemic climate risk into a tangible economic opportunity requires decisive action across both public and private sectors. For the Toilet Board Coalition, this means working across three interconnected areas: disrupting how sanitation is understood within climate policy, taxonomies and investment thinking; connecting entrepreneurs with corporates, investors and policymakers who can help unlock new opportunities; and accelerating proven sanitation businesses through tailored coaching, mentorship, investor readiness and access to capital.
But policy takes years to catch up, and the Sanitation Economy cannot afford to wait for taxonomies to be redrawn. The most immediate opportunity to drive change lies within the market itself, working in tandem with — not instead of — the public sector. Driving this transformation does not require inventing new, unproven technologies or untested theories of change; it simply requires scaling business models that already work. Suvidha, ECOSTP, Sanergy and Pluvia are proven, revenue-generating enterprises. The challenge now is creating the conditions, connections and capital required for models like these to scale. Closing that gap takes a mix of mechanisms: blended finance, which absorbs early-stage risk so private investors can confidently back a model once it has demonstrated commercial viability, sits alongside personalised business coaching, mentorship and investor-readiness support. This approach is central to the Toilet Board Coalition’s work.. To date, our Accelerator has graduated 111 SMEs, unlocked an estimated $49 million in investment, and matched grassroots entrepreneurs with the corporate mentors and capital providers required to reshape the sector.
As the economic costs of climate-related disasters continue to rise, strengthening resilient sanitation systems becomes increasingly important. By giving proven businesses personalised coaching, mentorship and crucial capital connections, the Toilet Board Coalition is helping build an ecosystem that can scale sanitation solutions and the economic, environmental and social value they create.
The Sanitation Economy is already demonstrating what is possible when sanitation is recognised not simply as a basic service, but as a source of economic, environmental and social value. If you are interested in joining the Toilet Board Coalition’s global network of partners working to accelerate this transition and scale the Sanitation Economy, we would love to hear from you. Reach out to us at info@toiletboard.org.
Sources
Dataintelo. (2026). Waste derived biogas market research report 2034. https://dataintelo.com/report/global-waste-derived-biogas-market
Lazzati, S., Ddiba, D., & Macura, B. (2024). Integrating sanitation and climate change in national level policy frameworks (SEI Report). Stockholm Environment Institute. https://doi.org/10.51414/sei2024.052
Ravi, M. (2024). Climate change and sanitation: A case for investing in intersectional impact. Toilet Board Coalition. https://www.toiletboard.org/climate-change-and-sanitation-a-case-for-investing-in-intersectional-impact/
Sanitation and Water for All. (2024). Climate action. Sanitation and Water for All.
Sanitation and Water for All. (2025). Presidential compacts on water and sanitation: Climate resilience strategies. Sanitation and Water for All.
Toilet Board Coalition. (2019). The Sanitation Economy. https://www.toiletboard.org/sanitation-economy/
UN-Water. (2021). UN-Water policy brief on climate change and water. https://www.unwater.org/publications/un-water-policy-brief-on-climate-change-and-water/
United Nations. (2014, November 19). Every dollar invested in water, sanitation brings four-fold return in costs – UN. https://www.un.org/sustainabledevelopment/blog/2014/11/every-dollar-invested-water-sanitation-brings-four-fold-return-costs-un/
Van Dijk, A. (2025). Global Water Monitor 2024. Australian National University / Global Water Institute. https://www.globalwater.institute/global-water-monitor-2024/
World Bank. (2006). The challenge of reducing non-revenue water (NRW) in developing countries: How the private sector can help. http://ppiaf.org
Author’s Note: Company-specific data presented in this article are based on self-reported information collected through the Toilet Board Coalition Accelerator.
