The S$6.5 million (approximately US$4.8 million) Carbon Zero Grand Challenge seeks to incentivize innovative solutions that can help PUB achieve net-zero emissions by mid-century and scale to water facilities around the globe. PUB is seeking carbon capture, utilization, removal, and other solutions at any technology readiness level that can be integrated with its operations and reach commercial scale within a decade or sooner.
The grand challenge will have two phases of competition and a pilot-scale demonstration over approximately 45 months. In the Proposal Phase, solvers will submit a detailed proposal addressing net carbon abated, cost, and other critical aspects of their solution. Up to six will be awarded S$250,000 each to develop a Proof of Concept. In the Proof of Concept Phase, solvers will develop a desktop simulation and/or lab-scale study and a detailed design for a pilot project. Up to two will be awarded S$2.5 million each to demonstrate a ~1 kiloton-scale version of their solution at a PUB facility in Singapore.
Click the Guidelines tab to learn more about this challenge and help us take the world’s water to net zero emissions and beyond!
As an island city-state, Singapore’s geography inherently limits its access to natural resources. For this reason, Singapore has always been an innovator and a leader in identifying clean, efficient, and cost-effective solutions for energy, water, and the environment.
PUB, Singapore’s national water agency, manages the nation’s water supply, water catchment, and used water in an integrated way. In 2020, PUB also took on the responsibility of protecting Singapore’s coastline from sea-level rise as the national coastal protection agency.
The global water sector contributes approximately 5% of greenhouse gas (GHG) emissions but has not yet received significant attention in climate debates. Although Singapore’s local water sector’s emissions represent less than 1.5% of the city-state’s total emissions, in today’s climate, every contribution counts.
The Sixth Assessment Report by the Intergovernmental Panel on Climate Change (IPCC) that was published in August this year, reinforced the reality that urgent and aggressive action is needed to keep global temperature rise below 2°C, as committed to in the Paris Agreement. Every sector must play its role, including the water sector. That is why PUB has set a goal to achieve net zero carbon emissions by mid-century.
The Carbon Zero Grand Challenge seeks to focus the attention of innovators, investors, and thought leaders on water sector emissions in order to accelerate the deployment of innovative solutions to address Singapore’s net zero carbon emission goals and scale to water facilities around the globe.
As an organization, PUB’s emissions in 2020 is approximately 460 kt CO2e as reported in PUB’s Sustainability Report 2020/2021. To achieve its net-zero goal, PUB will need to implement new technologies and solutions to address emissions associated with its water facilities. PUB has built a robust and diversified supply of water, including NEWater facilities that recycle used water and desalination facilities that convert seawater to drinking water (see FIGURE 1).
However, many of these processes are inherently energy-intensive and PUB’s emissions are projected to increase with population rise and economic growth in the coming decades. By mid-century, emissions could double to 1 MtCO2e.
PUB is already working to reduce its carbon footprint by replacing carbon-emitting energy sources with solar PV deployed on facility rooftops and at reservoirs, and reducing carbon emissions through energy efficiency, lowering desalination energy and conservation. These efforts are expected to abate approximately 600 kt CO2e/year of emissions by mid-century.
While current efforts can reduce PUB’s future carbon footprint substantially, PUB is seeking solutions to remove an additional 400 kt CO2e/year associated with its facilities that will require solutions such as carbon capture, utilization and storage (CCUS) and carbon removal (see FIGURE 1 and TABLE 1).
PUB Water Loop
Projected Emissions from PUB
Annual Estimated Projection
|Total PUB emissions|
1,000 kt CO2e
|Emissions for which solutions have already been identified|
600 kt CO2e
|Emissions requiring new solutions (focus of this grand challenge)|
400 kt CO2e
|Scope 1 emissions (within emissions requiring new solutions)|
200 kt CO2e
|Scope 2 emissions (within emissions requiring new solutions)|
200 kt CO2e
PUB’s projected Scope 1 emissions that will require new solutions (200 kt CO2e/year) are associated with its four water reclamation facilities and come from two sources:
FIGURE 2 illustrates a typical water reclamation process and the sources of Scope 1 emissions.
Typical Water Reclamation Process and Scope 1 Emissions
The remaining Scope 2 emissions (200 kt CO2e/year) are due to the electricity used to power PUB’s facilities, for example water treatment plants, desalination plants, NEWater Factories and used water treatment plants.
This grand challenge seeks solutions that 1) directly address emissions associated with PUB’s water facilities, as described in the section above; and 2) have the potential to be deployed at commercial scale within a decade or sooner. Such solutions may include:
Solutions that do not directly reduce or remove GHG emissions associated with PUB’s water facilities are out of scope for this grand challenge. These include:
The grand challenge will focus on accelerating the development of innovative concepts through proof of concept and an initial field demonstration. The grand challenge will include two phases of competition and a pilot-scale demonstration, as follows:
The grand challenge will last a total of approximately 45 months, including approximately 21 months for the two phases of competition and 24 months for the pilot project. TABLE 2 provides the expected timeline for the grand challenge.
Grand Challenge Expected Timeline
|Grand Challenge opens; Proposal Phase commences|
October 19, 2021
|Solvers register and develop submissions|
October 2021 – February 2022
|Proposal Phase registration deadline and submission deadline|
February 24, 2022
|Proposal Phase evaluation|
March – May 2022
|Proposal Phase awards announced|
|Proof of Concept Phase commences; Solvers selected to participate in this phase develop proof-of-concept submissions|
June 2022 to March 2023
|Proof of Concept Phase submission deadline|
|Proof of Concept Phase evaluation|
|Proof of Concept Phase awards announced|
|Pilot Project, including 6-12 months of operation|
Q3 2023 to Q3 2025
1 PUB is seeking to select a variety of solutions that address emissions in different ways to move forward to the Proof of Concept Phase and the Pilot Project Phase. However, the distribution of awards across solutions or types of technology will ultimately depend on the quality of submissions.
In the Proposal Phase and the Proof of Concept Phase, solvers must address the Key Performance Criteria for this grand challenge, as described in TABLE 3.
Key Performance Criteria for this Grand Challenge
Unit of Measurement
|Net carbon abated||The amount of CO2e permanently reduced or removed annually||-Expressed in CO2 equivalent (CO2e)|
|Cost||The projected cost per metric ton of CO2e abated for the solution at full commercial scale (100 kt/yr)|
-Expressed in S$/metric ton of CO2e
-Using the techno-economic analysis guidelines explained below
|Footprint||The physical footprint of the solution at pilot scale (approximately 1 kt/year) and at full commercial scale (100 kt/year)||-Expressed in m2|
For the techno-economic analysis, solvers should provide cost estimates that are reasonably accurate and precise, and presented in such a way that the major cost factors can be broken out and analyzed for error, uncertainty, and sensitivity. The analysis should include all costs over the life of the project on a levelized basis.
Solvers should calculate cost as follows:
S$/tonne of CO2e abated =
(Capital Expense plus Operating Expense minus Revenues)
divided by # of metric tons of CO2e abated
This grand challenge will offer up to S$6.5 million (approximately US$4.8 million)2 in awards and an opportunity to demonstrate a pilot-scale version of the solution at a PUB facility in Singapore.
Solvers will be selected for an award at the end of the Proposal Phase (up to 6 winners with S$250,000 each) and at the end of the Proof of Concept Phase (up to 2 winners with S$2.5 million each). To receive an award, solvers must accept the Conditions of Contract. See the Conditions of Contract template here. Solvers will not receive the total award funding upfront when the award is announced; rather, solvers will propose (and PUB will need to approve) a payment schedule based on key technical milestones for personnel and reimbursable expenses associated with activities that will be conducted in the subsequent phase. The payment schedule and reimbursable expenses will be part of the submission requirement for each of the two phases of competition.
For example, Solver A is selected for an award based on their Proposal Phase submission. Solver A is now eligible to receive up to S$250,000 over the course of the Proof of Concept Phase. In their Proposal Phase submission, Solver A proposed S$50,000 for reimbursable expenses and two payments for personnel based on technical milestones: one for S$50,000 that occurs when the lab-scale equipment has been set up and one for S$150,000 that occurs when Solver A submits their Proof of Concept Phase submission. If PUB agrees to this payment schedule and Solver A meets both milestones and provides receipts/invoices for the reimbursable expenses, Solver A will receive all payments, totaling S$250,000.
TABLE 4 summarizes the award distribution.
Award Distribution for the Grand Challenge
|Awardees||Total Amount Available||Amount Available Per Awardee||Payment Schedule|
|Proposal Phase Winners||S$1,500,000|
X 6 awards
|Based on milestones and reimbursable expenses proposed by the solver and approved by PUB; all milestones and reimbursable expenses must be completed by the Proof of Concept Phase submission deadline (March 2023)|
|Proof of Concept Phase Winners||S$5,000,000|
X 2 awards
|Based on milestones and reimbursable expenses proposed by the solver and approved by PUB; all milestones and reimbursable expenses must be completed by the end of the Pilot Project (Q3 2025)|
2 This amount reflects currency exchange rates accessed on October 6, 2021 found here: https://www.x-rates.com/calculator/?from=SGD&to=USD&amount=6500000
To participate in the grand challenge, solvers must:
To receive funding in this grand challenge, solvers must:
All elements of the Proposal Phase submission described below must be submitted by February 24, 2022, at 5:00 pm Eastern Standard Time. Note that any optional supplementary materials that are submitted may or may not be reviewed and considered, at the judging panel’s discretion. All character limits include spaces. Submissions must be submitted using the online submission form.
Section 1: Introduction
Section 2: Company Information: complete if submitting as part of a company
Section 3: Team Information
Section 4: Your submission
In the Proposal Phase, solvers will be evaluated on the submission elements described above. The judging panel will consider how well each submission element addresses the goals of the grand challenge (as described in the Background section of these guidelines), as well as the completeness and credibility of each element.
The weightage for each element is as described in TABLE 5. Up to the 6 best solutions will be selected for the award in this phase.
Weightage for each Submission Element in the Proposal Phase
|Rationale for the Solution and Innovation|
Development Plan and
Project Budget and Milestones
All elements of the Proof of Concept Phase submission described below must be completed and submitted by the deadline. This deadline is expected to be approximately nine months following the commencement of the Proof of Concept Phase. An exact date and time for the deadline will be posted on the grand challenge website following the announcement of the Proposal Phase awards.
Solvers will follow a template that will be provided after the Proof of Concept Phase commences
In the Proof of Concept Phase, solvers will be evaluated on the submission elements described above. The judging panel will consider how well each submission element addresses the goals of the grand challenge (as described in the Background section of these guidelines), as well as the completeness and credibility of each element.
The weightage for each element is as described in TABLE 6. Up to the 2 best solutions will be selected for the award in this phase.
Weightage for each Submission Element in the Proof of Concept Phase
|Description/Results of Proof of Concept|
Proof of Concept Performance
Development Plan and
Project Budget and Milestones
You won't want to miss this! Join the Carbon Zero Grand Challenge webinar tomorrow!
You will learn exactly why PUB launched the Carbon Zero Grand Challenge, how you can participate, and what you can win. PLUS you will also have the opportunity to ask the Challenge Sponsor your questions during our live Q&A session. See you there!
(Please note that both Sessions will cover the same content and are set to accommodate different time zone options for participants. There is no need to attend both Sessions.)
You won't want to miss this! Join the Carbon Zero Grand Challenge webinar.
You will learn exactly why PUB launched the Carbon Zero Grand Challenge, how you can participate, and what you can win.
PLUS you will also have the opportunity to ask the Challenge Sponsor your questions during our live Q&A session. See you there!
If you have yet to read up on what happened at COP26 - we have you covered! Head on over to the HeroX blog and check out the latest post which outlines the "5 Key Insights from COP26". Feel free to drop your thoughts in the comment section.
Sign up for our upcoming Q&A webinar here!
Please note that both Sessions will cover the same content and are set to accommodate different time zone options for participants. There is no need to attend both Sessions.