Green Bonds. ESG Ratings. Credit Risk. Who Can Investors Trust? Find the Answers at the Sustainability and ESG Africa Conference.

South Africa is laying the groundwork for its first sovereign green bond — a significant development for the country's sustainable finance market and a potential new mechanism for mobilising capital towards the transition.

But behind the headline sit some much bigger questions for banks, investors, asset managers, insurers, CFOs, treasury professionals and business leaders.

Who decides what qualifies as sustainable? How should sustainability performance influence credit risk and the cost of capital? How reliable and comparable are ESG ratings? And, ultimately, who rates the raters?

These are exactly the kinds of questions that will be put on the table at the Sustainability and ESG Africa Conference, taking place on 30 September and 1 October 2026 at the Sandton Convention Centre.

As South Africa looks towards the next generation of sustainable finance, the conference will bring together leaders from business, finance, investment and sustainability to examine not simply whether ESG matters but how sustainability is influencing risk, investment decisions, access to capital and long-term economic value. “This is where the sustainability conversation is increasingly becoming a business conversation”, says Kudzayi Mazikana, Head of Sustainability at Nedbank Business and Commercial Banking. “For businesses, the question is no longer simply how they report on sustainability, but how issues such as energy, water, resource efficiency, and climate resilience affect competitiveness, operating costs, risk and ultimately capital.”

A potential new chapter for South African sustainable finance

National Treasury is reportedly laying the groundwork for a debut sovereign green bond, potentially within the fiscal year ending March 2027, subject to factors including the availability of an appropriate project pipeline and market conditions.

The potential issuance comes against an enormous financing requirement.

South Africa is estimated to require approximately R3.7 trillion between 2026 and 2035 to support climate mitigation and adaption. That capital needs to come from somewhere. ”The scale of the requirement is significant, but South Africa’s transition will not be financed through sovereign funding, capital markets and large infrastructure projects alone”, says Kudzayi Mazikana. “A meaningful part of the transition will ultimately take place in the real economy, through investment decisions made by businesses around energy, water, production systems, resource efficiency and resilience.”

Government cannot finance the transition alone. Banks, institutional investors, pension funds, development finance institutions and private capital will all have an increasingly important role to play.

A sovereign green bond could therefore represent much more than a new government funding instrument. It is another indication that sustainability considerations are moving closer to the heart of capital allocation and financial decision-making.

And South Africa's private financial sector has already begun demonstrating what this evolution could look like.

From sustainability ambition to sustainable capital

In 2019, Nedbank became the first South African commercial bank to launch a green bond on the JSE, raising R1.7 billion to fund renewable-energy projects.

Since then, sustainable finance has expanded considerably, encompassing green and sustainable bonds, sustainability-linked loans and other financial instruments designed to connect funding with environmental and social outcomes.

Mazikana says that the next evolution is increasingly about connecting those financing mechanisms to measurable business outcomes. “For a commercial business, sustainability becomes particularly relevant when an investment can strengthen resilience, improve efficiency, or address a material risk. The financing conversation then becomes much more tangible.

That brings us to one of the most challenging issues facing the ESG and sustainable finance ecosystem.

Who decides what is credible?

ESG ratings and credit ratings can influence how markets understand companies, governments, investments and risk. Yet ESG ratings in particular have attracted considerable scrutiny internationally because different providers can reach very different conclusions about the same organisation.

Part of the challenge lies in the way these assessments are made. Methodologies, indicators, weightings and data sources can vary significantly between providers, as can interpretations of what constitutes material ESG risk. The result is that an organisation may perform strongly according to one assessment and considerably less favourably according to another.

For investors deciding where and how to allocate capital, these differences matter. They also matter for companies seeking to understand how their sustainability performance is being interpreted by markets and how those perceptions could influence investment, financing and risk decisions.

For African economies, the stakes are potentially even higher. The continent is competing for global capital at the same time as it requires significant investment in infrastructure, climate resilience, the energy transition and sustainable development. If assessments of risk and sustainability can influence investor confidence and potentially the cost and availability of capital, then understanding how those assessments are reached becomes increasingly important.

Which raises a deliberately provocative question:

Who rates the raters?

At the Sustainability and ESG Africa Conference, this question will be tackled directly in the session:

Who Rates the Raters? ESG Scores, Credit Risk and the Power of Rating Agencies

The debate will ask whether rating agencies are helping markets price sustainability risk properly — or whether inconsistent scoring, opaque methodologies and commercial incentives risk distorting investment and financing decisions.

Joining the discussion will be:

Ted Maselesele, Treasurer, African Credit Rating Association & and

Obed Mbuzi, Vice President, African Credit Rating Association

Their participation also introduces another important dimension to the conversation:

Who decides what deserves the money?;These aren't theoretical ESG questions anymore. They are financial questions.

From ESG reporting to financial performance

This shift sits at the heart of the Sustainability and ESG Africa Conference 2026.Across two days, the programme moves the sustainability conversation beyond reporting and compliance to examine its relationship with capital, competitiveness, resilience, risk and business value.

South Africa's proposed sovereign green bond makes that conversation particularly timely.

On 30 September and 1 October 2026, the Sustainability and ESG Africa Conference will bring these conversations into one room at the Sandton Convention Centre, Johannesburg.

Apart from two days of conference content with over 100 leading industry speakers, the event will also host the 4th edition of the ESG Student Innovation Competition, the Beyond Awards, the Sustainability Exhibition, and the 5th edition of the YES ESG Awards, recognising the youth and celebrating sustainability and ESG excellence in Africa. On the first morning, top corporate leaders will join the Leadership Summit, and the second morning will host the 2nd edition of the SMME Summit. Two days of learning, inspiration, and networking.

It is no longer simply what is your ESG Score but questions like what does your score actually tell us and can markets trust it and what does it mean for risk, investment and insurers.