From Marginal Land to Baseload Power: How OPUS Cactus Is Turning Cactus into Energy

South Africa’s energy crisis has forced government, investors, corporates and policymakers to look beyond traditional solutions for reliable, low-carbon baseload power. While wind, solar and liquefied natural gas (LNG) dominate the conversation, a less obvious contender is emerging from the country’s semi-arid interior: biogas produced from cactus grown on marginal land.

OPUS Cactus, a biotech company operating between South Africa and the Netherlands, demonstrates that the drought-tolerant spineless Opuntia cactus can unlock decentralised baseload energy in regions long considered uneconomical — while simultaneously creating agricultural, food and carbon value. If the model scales as planned, it could reshape how energy, land use and rural development intersect in South Africa.

At a time when the country is grappling with grid instability, constrained infrastructure and rising energy costs, OPUS Cactus is positioning itself not as a speculative climate-tech startup, but as a long-horizon infrastructure and bio-economy play grounded in physical assets and on-the-ground proof.

What Is OPUS Cactus? A Biogas and Regenerative Agriculture Platform

OPUS Cactus is a bio-based technology company focused on cultivating Opuntia cactus on semi-arid and marginal land and converting the biomass into biogas and other downstream products. Its approach sits at the intersection of regenerative agriculture, renewable energy and long-term land value creation.

OPUS Cactus is headquartered in the Netherlands, where its laboratory and core research capabilities are based. Its primary agricultural research and operations are in South Africa. The company operates a large-scale cactus farm near Bloemfontein in the Free State, which serves as both a commercial operation and a research and development site.

“We valorise the plant through mainly biogas production and biogas to other downstream valorisations, but also fruits and animal feed,” said Joeri van den Bovenkamp-Hofman, CEO of OPUS Cactus.

The business has been deliberately structured around long-term physical assets rather than short-cycle technology bets. For investors used to software or platform models, this represents a markedly different risk-return profile — one tied to land, biological systems and infrastructure rather than rapid user growth.

Van den Bovenkamp-Hofman, who joined OPUS Cactus in March 2024 after more than 15 years as an entrepreneur in the IT sector, said the move reflected a desire to build something tangible and sustainable.

“I wanted to do something more sustainable, something more tangible instead of ones and zeros,” he said. “This is absolutely tangible.”

Why Marginal Land Is an Untapped Asset for Energy Investors

Much of South Africa’s semi-arid land has historically been written off as agriculturally unproductive and economically marginal. That perception has shaped where infrastructure is built, where capital flows, and which regions are included in energy planning. 

OPUS Cactus is challenging that assumption by targeting landscapes where conventional crops struggle but cactus thrives. And, by demonstrating that these areas can support productive, multi-use systems rather than single-purpose extraction. 

“If you target semi-arid regions for cultivation, it usually means there are not a lot of economic possibilities in those areas,” van den Bovenkamp-Hofman explained.

The Opuntia cactus offers a fundamentally different yield profile compared to traditional grasslands, particularly in the Free State. In the Bloemfontein region, grasslands yield roughly one ton of dry biomass per hectare in a good rainfall year. Opuntia, by contrast, produces a multiple of that on the same land area.

“This plant yields 35 to 45 dry matter tonnes per hectare, whereas the grasslands there yield at best around one ton,” he said.

That productivity gap is central to OPUS Cactus’s thesis. Higher biomass yields translate directly into greater biogas potential, improving project economics and reducing land-use pressure elsewhere. In a country where arable land is finite and water scarcity is a growing constraint, that distinction matters.

Crucially, the company is not competing with food crops for prime agricultural land. The cactus thrives in conditions that would otherwise offer limited economic return, allowing OPUS Cactus to position marginal land as a productive asset rather than a liability.

From Cactus Biomass to Reliable Baseload Power

South Africa’s renewable energy debate is often framed around intermittency — what happens when the sun does not shine or the wind does not blow. Baseload power has traditionally been the domain of coal, gas and nuclear, with renewables seen as supplementary rather than foundational.

Biogas challenges that distinction.

Biogas and Biomethane as Dispatchable Renewable Energy

By converting cactus biomass into biogas and upgrading it to biomethane, OPUS Cactus aims to produce a continuous, controllable energy source that operates independently of weather conditions. That gas can then be converted into electricity on site using combined heat and power systems, or supplied directly to industrial offtakers where appropriate.

The model is particularly relevant for mining operations and remote industrial users operating far from major grid infrastructure - a common reality across large parts of South Africa.

“You could actually have your baseload power as a mining company, while also offering economic opportunity in those regions,” said van den Bovenkamp-Hofman.

Decentralised Power for Mining and Industrial Offtakers

In mining regions, the implications extend beyond energy supply. Cactus plantations can create agricultural employment in areas with limited alternatives, while providing an energy solution that remains viable even after mines close.

“At a later stage, when mines close, you can continue supplying power or move into other valorisation pathways,” he said.

That flexibility — energy first, with optional transitions into animal feed or food production — is a recurring theme in the company’s strategy.

Competing with LNG Without Feed-In Tariffs

Unlike Europe, South Africa does not have a mature national gas grid or a comprehensive feed-in tariff framework for biogas. Those absences present clear structural challenges for developers — but they also shape OPUS Cactus’s decentralised approach.

“There’s no feed-in tariff system and no programmes stimulating biogas production,” van den Bovenkamp-Hofman said. “You’re competing at LNG import price levels.”

The lack of infrastructure means projects must be designed to consume energy locally or convert gas into electricity or transportable formats such as compressed or liquefied gas. While this raises complexity, OPUS Cactus believes it is already competitive with imported LNG from a pricing perspective, even without policy incentives.

In Europe, where gas grids are well established and biogas markets are mature, similar projects benefit from structural support and easier market access. In South Africa, OPUS Cactus is instead building around decentralisation, industrial offtake agreements and long-term project finance — effectively working around the constraints rather than waiting for policy to catch up.

A Long-Term Infrastructure Investment Built on Living Assets

One of OPUS Cactus’s core advantages is the longevity of its feedstock. Opuntia is a perennial crop with a lifespan well beyond 30 years. For project finance purposes, the company models energy production over 20-year periods, with multiple post-energy pathways available.

After energy production, plantations can be repurposed for animal feed, food production or other bio-based applications. Because only a portion of the plant is harvested at a time, the root system remains intact, supporting soil health and long-term carbon sequestration.

“This is a completely different investment profile compared to IT or software,” said van den Bovenkamp-Hofman. “You’re building tangible assets, long-term cash flows and increasing the value of the land itself.”

For investors accustomed to shorter exit horizons, that distinction is important. OPUS Cactus is targeting institutional capital, long-term-focused venture funds and corporate investors that are comfortable with multi-decade infrastructure-style returns.

Proof on the Ground: Scaling Biogas from Waterkloof

Agricultural and climate-tech projects in Africa often face scepticism from investors, particularly those burned by under-delivering pilots or overly theoretical models. OPUS Cactus has taken a deliberately different approach.

“The best way to sell this to investors is to invite them to Waterkloof and let them see it with their own eyes,” van den Bovenkamp-Hofman said. “We’ve done the trials, the piloting and gathered the data to support what we’re saying.”

The Waterkloof site near Bloemfontein functions as both a production asset and a skills development hub, addressing another gap in South Africa’s biogas ecosystem: technical capability. While biogas is a mature industry in parts of Europe, the skill base in Southern Africa remains limited, often requiring expertise to be imported.

By producing biogas locally and building operational know-how on site, OPUS Cactus is positioning Waterkloof as a foundation for scaling future projects across the region.

Expansion Strategy Across Semi-Arid Global Markets

OPUS Cactus is currently in a funding round targeting institutional investors, long-term-focused venture funds and corporate partners, particularly from the energy, mining and food sectors. The company aims to bring multiple South African projects to financial close, with a strong focus on gas production.

Beyond South Africa, OPUS Cactus is exploring expansion into other semi-arid regions, including parts of sub-Saharan Africa, the Middle East and southern Europe. Any expansion will require local nurseries, as cactus plantations are propagated from cuttings rather than see - a factor that naturally slows reckless expansion but strengthens long-term project viability.

The company is also collaborating with mining partners on land rehabilitation initiatives, using cactus cultivation to restore degraded or previously mined land while creating new economic value.

The Cascading Biorefinery Model

Looking further ahead, OPUS Cactus’s vision extends beyond bioenergy alone. The company is developing a cascading biorefinery model in which higher-value compounds are extracted first, with remaining biomass converted into energy, creating a circular system.

“Our vision is a cascading biorefinery in semi-arid landscapes,” van den Bovenkamp-Hofman said. “Extracting value first, then valorising the remaining biomass through biogas, while maintaining carbon-neutral land use.”

In a country searching for scalable, resilient and decentralised energy solutions, OPUS Cactus is betting that the future of baseload power may be growing quietly on land most people stopped paying attention to decades ago.