Net-zero from Kivu’s Renewable Gas: 1 Essential but Complex Need

Is Africa’s Lake Kivu a huge CCSU? Can it double-up energy production with storage?

We attribute “net-zero from Kivu’s renewable gas” because a series of Kivu projects achieve that for Rwanda and for Eastern DRC. So Kivu evolves into a hydro energy battery, on top of being the world’s largest RNG bio-digester. It does much more than double-duty for energy storage and energy production.

It’s a 500 cubic km water reservoir elevated 700 m above Lake Tanganyika for hydro and stores that same volume of renewable gas. And there’s more. It can produce RNG for 600 MW power, with 576 MW of hydropower and can turn stored CO2 into 1 M tpa of ethanol for renewable fuel.

It naturally performs a complex CCS duty of storing gigatons of carbon. Our projects enable 2 gigatons of carbon emission reductions by preventing a build-up to a major gas eruption. Its hydropower potential to generate 576 MW of load-following, run-of-river power on demand. Add ethanol from CO2 and this now becomes a phenomenal nature-based solution, that lowers the cost of energy dramatically. It can also halve fossil fuel imports. It can halt or reverse deforestation. It’s a country-scale CCS, upgradeable to a giant among CCSU systems, and then a whole lot more. It’s a holistic journey to net-zero from Kivu’s renewable gas and all these other achievements.

It’s so complex it defies conventional clean energy “taxonomy”

Lake Kivu’s has an extraordinary list of cleantech credentials. It complicates the simple job of filling the project information questionnaire. “Which type of cleantech project is this? Pick one.” We need to tick off a series of boxes on a checklist that always demands one choice. It straddles as many as 6 categories. When investors demand a simple label, how do we help them out? They won’t like “It’s Complex”.

So how does this Complex Solution become recognised in the climate change lexicography? Nature has provided the potential solutions to get the countries neighbouring Lake Kivu beyond carbon neutral. Are we going to trip up on naming it? It stands alone in this “really-good-for-the-planet” category of climate solutions. How can it also help this gorilla’s habitat survive and thrive?

The carbon-negative renewable natural gas contribution

We illustrate this lake as a leading example of how “Carbon negative” projects can be the super-achievers in the great climate challenge of our times.

Even methane from cattle can become part of the solution. Let’s break this argument down further. RNG is known for providing carbon-neutral energy. Take biogas from agricultural waste, where the USA is targeting 40 megatons of carbon reduction by 2030. This one project on Lake Kivu in Rwanda and DRC achieves the USA’s RNG target by itself.

So how does gas recovery prevent gigatons of natural background carbon emissions? What if we can add a side benefit of reversing destruction of vast equatorial forests to keep that carbon sink viable? This nature-based solution helps preserve the mountain gorilla’s habitat and a pristine lake, while exceeding net-zero. In reality these benefits are a step-up, adding to being carbon negative. So “RNG Neg” can be a vital, although an easily overlooked climate change solution. The solution has huge scaleability by doing far more than cutting methane emissions.

Let’s look at this specific methane source, created by nature without human intervention. Importantly, this a case is where one can both extract natural biogas and reverse carbon emissions. As the add-on in this special case, it can replace forest biomass as the region’s primary domestic fuel within 10 – 15 years. This change in fuel takes deforestation pressure off the mountain gorilla habitat in the Virunga Mountains in Africa. So RNG is an opportunity helping to buy time for the gorilla habitat and recreating a vast carbon sink.

How carbon-negative is this renewable solution?

More than that, the graphic below shows how we get to the hoped-for impact of buying time in the Climate Change context. Compare it to other methods listed for negative carbon emissions. Most lack much capacity or even credence, requiring thousands of them to make a mark. Well, this unusual one wasn’t on the list. It should be in time, not just as a one-off.

Climate activists commonly advocate that natural gas is not “low-carbon” enough and not part of the climate solution. Natural gas suppliers field demands to remove any claim of having real “low-carbon” investments. The louder calls are to advocate the use of hydrogen, or PV or wind. But while hydrogen is in many ways an ideal fuel, it comes with user difficulties, dangers of explosion and higher supply and distribution cost. It’s costly to transport, has low energy density and is near impossible to move by old pipelines.

We should differentiate clean methane sources from conventional, fossil “natural” gas though. Some of them, like our projects, can even be strongly negative on carbon emissions. That’s a long way better for the planet than neutral.

Purpose for Kivu gas extraction is evolving

The original Hydragas solution was a needs-driven innovation. It was created to deal with a looming threat at unprecedented humanitarian and environmental levels. Without acting on this threat in our lifetimes, millions of lives were at risk. The negative outcome is also a one-time, catastrophic environmental hit. We can avert this one-day, 2-6 gigaton carbon emission by preventing lake Kivu erupting. In a relative priority sense, the climate impact is a bonus on top of all these lives saved, but meaningful on a global scale.

Now sometimes we may think we have a great invention to talk about. But more importantly, to market it for investment, should we frame it in terms that resonate? Ours has been a 20-year pioneering, technological pursuit. So it isn’t just any cleantech project using available innovative technology. We now know it to be carbon negative. So it stands out as a high-impact climate changer with added carbon sequestration value.

It took a decade to figure out how to do this project safely and effectively. We filled a need where suitable recovery technology did not exist. It overtook an older, flawed extraction idea and turned it around with an inventive breakthrough.

Our motivation was at first about solving a gas extraction problem. Then it became about saving lives. Then it grew to add the need of turning around carbon emissions. The line must now be: “It saves millions of lives, averting gigatons of carbon emissions, a nature-based solution making a country or two carbon-negative”.

Labeling is key; Can we call it a grid-scale battery, CCS?

How is it going to sell the concept to investors? So should we re-frame it further? We can make it focused on the climate change problem of the day – energy storage. Should we now claim how; “We see Lake Kivu as a giant battery caspable of 263 TWh of renewable energy storage.” We can add that; “This battery trickle-charges itself at 2,600 GWh per year.” What is the key data to place with that label? Renewable gas can produce 600 MW of clean power for next fifty years.

Like a good battery we can stretch it out longer though. Look after it and it never degrades. We still have the urgent, initial need to drop the danger level of gas build-up, for say 25 years. Then we could then produce over 200 MW of renewable, clean power for centuries.

Add a 576 MW hydro-power investment to the same lake

But there’s more to add to this “battery”. This same lake has been producing 18 MW of hydro power, from an old run-of-river station at its outlet, for over 50 years. The Ruzizi river cascade drops another 700 metres to Lake Tanganyika just 50km south of the lake’s outlet. A series of dam-free hydropower projects on this cascade can also deliver 576 MW. So the two projects in combination can yield 1200 MW for the next 25-50 years. The longer view is perhaps for over 800 MW in perpetuity. That’s one big, long-life battery!

An equatorial lake and a volcano,  a recipe for an energy opportunity or a nightmare
An equatorial lake and a volcano, a recipe for an energy opportunity or a lurking nightmare?

So “whose definition is this definition?”

As we hear in the climate debate, any “natural gas” label is in a contentious basket of climate value. It is grouped, and assumed to be formed, with its fossil relatives coal and oil. Let’s flex a defining piece of that narrative. In talking of semantics and messaging, what of biogenic gas? Does Mesozoic-age fossil-formed gas rank the same as “fresh” biogas from cow manure in bio-digesters? They are both GHGs. Its formation followed similar pathways, millions of years apart. I studied this comparison with some global experts. Today our conclusion must be that RNG best categorises itself as carbon-negative renewable gas.

That’s not the end of the argument either. In an ongoing review of the Lake Kivu MPs, governing the lake’s use, some reviewers would like to have a new take. Their view is any biogas already in the lake today is “fossil”, but from tomorrow any additional naturally produced biogas is “renewable”. What crappy, revanchist thinking is this? It is one pool of carbon-negative renewable gas.

The case for biogenic, renewable status

The carbon dioxide and methane in Lake Kivu in Africa is biogenic. It’s freshly brewed. Algae consumes dissolved carbon dioxide to grow biomass. Biomass biodegrades in anoxic depths to make methane and carbon dioxide. It uses the acetate process and also methanogens. The world’s largest bio-digester is part of a cycle making carbon-negative, renewable gas. Can we continue down this defining path and call it a bio-battery, powered by carbon-negative renewable gas?

CCUS: Is it a bio-battery, a bio-digester?

Most of the gas in Lake Kivu now in situ is less than a hundred years old. A resource of two gigatons of CO2e is already present. The bio-digester accumulates new gas at another 0.5% a year. I verified this storage calculation by completing the formal spreadsheet, while writing up a proposal for Breakthrough Energy Ventures competition. It is one of a number of initiatives where I looked for funding for the Lake Kivu project.

The essential action on us now, with a GHG reserve building up, is to first harvest it to make it safe. The second it is to combust that methane in power generation or in home cooking. A third action can be to re-absorb the carbon dioxide made, into the deep lake. Here it is substrate for microbiology that can turn back to methane. A virtuous green cycle is thus possible. Again, it sounds like it works as a battery. Like any battery, its design and operation have room for enhancement. We could speed it up, but with due caution.

So we can treat it like a giant battery. We keep it in reserve and deplete it when we choose to and we are able to. We are now capable to do it safely, finally. Now is the time we must do it urgently to constrain climate change.

Defining CCUS, or is it CCSU?

Must we prove to skeptics that it’s renewable and it has negative emissions? I met recently with Foresight, a group that champions clean energy solutions. I had this question: “If the gas is naturally biogenic, but not extracted continuously, is it still renewable?” The answer is yes, becasue it can be stored. But that answer would not be so if it leaks out to atmosphere. But in this case it’s fully trapped. This is a huge, natural CCUS reservoir that can store 450 bcm of gas (at the safe-side limit). It is the definition of Carbon Capture, Usage and Storage (CCUS). But now I’m seeing CCSU in the literature. Is it not the same thing?

What is the risk if we don’t harvest this lake gas?

Actually, we must first deplete this reservoir (or battery) by 50% now for safety reasons. That is why we must extract methane for the next 25 years to use up half the partial pressure (or volume) of gas in place. Thereafter we can discharge it indefinitely at a lower rate, closer to its natural recharge rate. That would be sensible. But our first order of business lowers the risk of eruption by a factor of two. It makes the lake 100 times safer. 99% risk reduction. We do this by depleting gas from the upper portions of the layered lake’s depths. These portions give rise to the gas in-situ most at risk, as they have the highest partial pressure.

With some caution we can research further into “farming” gas generation. We understand the micro-biology and bio-chemical engineering pathways of using the returned CO2 to generate new methane faster. Key to these actions will be in managing the nutrients flowing to the shallow biozone to enhance algae growth. This is done by water lifted from the nutrient-rich depths. That is the key to multiplying the energy potential in the long-term.

Safety Action: Preventing a catastrophic lake eruption

This is a very high-stakes resource management game. Those gigatons of gas, if left until they saturate the lake’s capacity, will erupt. The world’s limnology experts describe the mechanism as a limnic eruption. It’s much quieter, almost silent, but could be 50 times more deadly than Krakatoa’s explosion in 1883. Many casualties may result from lake tsunamis caused by a giant, surging column of gas and water. Waves would radiate out to the lake’s shores. But it’s the toxic and asphyxiating blanket of cloud that follows, emanating from that erupting column that is much more deadly.

So, gas extraction is our pre-emptive action to mitigate a catastrophe. It has to be done properly, with precision and care. Some amateurish and ill-considered legacy methods were used and more were planned. These attempts were worse than doing nothing. They break all the safety rules and bring the danger of eruption forward. The worst aspect of legacy methods is the deliberate breakdown of the lake’s multi-layered density structure. This structure was formed slowly over hundreds of years, strengthening to form a perfect trap for gas forming below.

The lake’s long-term safety plan is still built on a concept of removing the bulk of the lake’s methane in 50 years. After the first harvest, we may pause for perhaps 100 – 150 years to allow gas to regenerate. As the methane inventory reaches a viable concentration again, we begin to extract once more. That’s still in the harvesting plan. The concept is written up in the rules for how Lake Kivu must be developed. But a review in 2019-2020 revisited some of these options.

What carbon is in the envelope we evaluate?

The gases are produced biogenically in the world’s largest, contained bio-digester. Lake Kivu became one of the largest, manageable carbon sinks over millennia. I wrote it up in a breakthrough ventures application. I worked out the data in a painfully complex spreadsheet. It is a government-designed calculator to determine the carbon SSRs. There were guidelines. i.e. Use ISO 14064-2 Section 5.3 “Identifying GHG sources, sinks and reservoirs relevant to the project”. It was highly explicit about every value to be used.

I had already worked out the answer in 20 minutes by normal means. It took 150 hours using this standardized government-style spreadsheet. The answers were 1.01% different. The specified calculator gave the modestly higher answer. This is miniscule compared to the arguable range of tons CO2 per ton of CH4; the currently published range is between 25 and 103. There is a long explanation about which number applies when, based on when the reduction is most needed. For simplicity the calculator used 28. Using this range the averted carbon emissions varies from 1.9 to 6.3 gigatons. The high end of this range is very close to the total annual US emissions in 2014, published by the EPA, of 6.89 gigatons.

Why make it so complicated? Was it to ensure one didn’t cheat? In essence it defines the full envelope. It assesses GHGs and SSRs with a cumbersome methodology. One even includes the GHG impact of building and then demolishing the equipment. One must account for displaced energy when switching to a new source. It presents the data in a spreadsheet common for all applicants. But getting it done is way worse than doing your taxes. The outcome still shows this renewable gas is carbon negative.

Proving renewable gas is carbon negative

The adjacent figure (click on it to expand) shows L-R the improving trend of power generation from coal to natural gas. Hausfather presented the data to show the US power industry gains from replacing coal with natural gas. I added the final bar to show how the proposed Lake Kivu project outperforms. The linked article questions if natural gas is a bridge fuel to renewables. I would argue that RNG is itself a game changer that goes much further than carbon neutrality. But how can these special cases be replicated on a global scale? There are opportunities for scale-up of averting major emissions in my next post.

I added the final bar to show how the proposed Lake Kivu project outperforms. The linked article questions if natural gas is a bridge fuel to renewables. I would argue that RNG is itself a game changer that goes much further than carbon neutrality. It transforms from being a clean gas source to the most powerful, renewable battery out there.

But how can these special cases be replicated on a global scale? There are opportunities for scale-up of averting major emissions in my next post. That means going after the biggest resource of all, methane in the oceans.

Let’s not forget how to help the gorillas

But let’s not forget the gorillas. Before even considering deforestation, Africa’s equatorial forests are under threat and so is the gorilla’s mountain domain. Apart from land pressures, the region still uses firewood and charcoal for 80% of its non-transport energy needs. Any action that reduces deforestation is also about protecting their shrinking domain. RNG will help, so let’s make carbon negative renewable gas.

What message sells to investors?

This project needs investment. This type and scale of project is desperately needed. People need to be assured of safety where they live. The gorillas need their forest back. So now we need to pitch the investment, but also the back story to investors. The question is how? It’s a great impact investment with high returns. But for investors? They’re a skeptical lot, as they must be. Any claim we can make to amp up a valuation has to be discounted or countered by them when negotiating an investment deal.

This much carbon mitigation (whether 40 or up to 130 megatons per year) can be worth a lot. The Canadian government has priced carbon at CAD 150/ton. Imagine if we could sell that for $600 M a year. So, inevitably as founders, we should get quizzed on this point. And so it has been. We like to appeal to the investors’ better selves too, with the humanitarian and environmental impacts that are the real drivers. The Lake Kivu project has huge impact. The priorities are first to people safety, then to the environment and finally to the community’s bottom lines.

How to sell “carbon negative renewable gas”?

As an aside, I would be interested in the stats on this. How many pledges are made to fund renewables? As many as are calling on others to do the funding? How many are calling for funding negative carbon projects or for countries to go net-zero? I have seen hundreds. Is it a facile way to get position on the bandwagon? What ever came of Canada’s Prime Minister’s 2015 pledge at COP-21 in Paris to fund $2.6 B of clean energy projects in the developing world? How much more is being promised at COP-25 in Madrid? What is expected at COP-26 in Glasgow.

On the other hand, how many of the valid cleantech start-ups with projects eventually do get funded? Worse still, how many are not? Who, among many innovators and developers, crosses the proverbial “valley of death” illustrated here by FCA? Where do these developers, looking and pitching for these funds, get the money? Their enthusiasm is more evident than that of corresponding investment funds. For that answer, it’s probably from intermediaries.

The role of the intermediary, the aggregator

This clean energy funding marketplace has seen a proliferation of financing intermediaries. They are aggregators of new project prospects, those start-up’s prospects that couldn’t afford to present at all the conferences. Is this changing now with COVID-19 taking conferences virtual?

Intermediaries don’t raise funds as start-ups, but to aggregate. They step in, providing aggregating vehicles to reduce the hard work for bigger funds as a conduit for hard-to-pitch-for funds. They are able charge fees for their disbursement of other people’s money to projects. In doing so they are earning a 5% slice of the investment without carrying all the downsides of failed investments. They also secure rights to step up investment later at a discount. It’s a sweet gig.

Changing tactics in the time of COVID-19

Perhaps the tactic for start-ups and developers lies in two complementary pathways. First is to present themselves more often at these virtual fundraising events. The formerly prohibitive cost of attending is down by 90%. Secondly is how to frame our projects better for primary investors.

What now of the intermediaries? What will they want to invest in and what makes them worthwhile as intermediaries? Start-ups need to connect with them in a way that works. So let’s present our options as Hydragas. Let’s label Lake Kivu as the promising niche that it is. Let’s see if that is as a giant energy storage system or series of clean projects with gigatons of carbon-negative emissions reduction.We’ll colour it any way the market wishes, as long as we get to fund it. Some ways just cost more than others, but that’s still way better than lingering on zero investment.

3 thoughts on “Net-zero from Kivu’s Renewable Gas: 1 Essential but Complex Need

Leave a Reply

Your email address will not be published.