Lake Kivu 3D Stallite image by Christoph Hormann gas-to-power

Climate change: Clean energy in Rwanda’s future

Gorilla image formed by the clouds abobve Mt Nyiragongo in the DRC
Spot-the-Gorilla: image formed by volcanic steam above Mt Nyiragongo in DRC

Few countries have achieved a totally clean energy future on non-transport energy. Germany tried with its Energiewende for 20 years. Norway has had that status for years. But Germany wanted a full transition to clean power by 2020. Michael Schellenberger of Der Spiegel questions its failings and why. With a year to go it’s achieved only 25% of it. Was it asking too much, too soon? So if not Germany, who then could do it soon enough to meet climate change goals?

How a country makes a clean energy future?

My view is that for that same ambitious clean energy plan, Rwanda can do it too. Yes, and quicker too. Ironically it’s Rwanda’s lack of coal and oil that helps the country get to it faster. We know the country has a wish to achieve this clean energy future. But what about the means? It’s not as though Rwanda has the industrial power and capital of Germany, it clearly doesn’t.

But it has two key things: (1) Few of the wrong-choice power systems already in place, and (2) several transformational clean energy assets like hydro-power. The country can make that future a reality without over-crowding its landscape with wind turbines, solar panels and too many interconnecting power-lines. Rwanda has truly beautiful landscape. It does not need that sort of blot on its scenery. For that matter, it doesn’t need the noise of turbine blades disturbing the incredibly quiet nights. Noise would especially disturb the windier mountain domain of the gorillas, a global treasure.

The scope of the energy transition to clean power

Political Map of Rwanda showing Lake Kivu Location
Map showing Rwanda with Lake Kivu location

Indeed the country, together with the Kivu provinces of DRC, can build a sustainable, clean energy future. Better still, it would soon have built a surplus for export to other neighbours in East Africa. In fact Rwanda can pass this key tipping point to a clean energy future in about five years. The idea is fully sustainable for over half a century. In the same 5 years they can demobilise the hired temporary-power systems that runs on imported diesel. With enough clean power installed, once the existing HFO-fueled power plant is placed on standby, the country can run on clean power alone.

Hydro power and RNG power for a clean energy future?

So this region is poised to be a clean energy bright spot in the heart of Africa. One key resource enabling their sustainable, clean energy future is Lake Kivu. It’s energy potential is a unique case among Africa’s Great Lakes. It’s a high-altitude source for both hydro and renewable biogas energy (RNG). But there is a greater differentiator for this energy source. This is where nature has taken a millennium to craft a unique, water-borne gas reservoir.

Think of Kivu as a giant, clean battery that was a gift from nature. Its combined hydro and gas potential can supply up to 1200 MW. This extends for over 50 years and beyond. In terms of energy already stored in Kivu’s gas reserves, it is the equivalent of a 260 TWh battery. Nature is “trickle-charging” this battery at the rate of 2600 GWh per year. That’s huge. The lake’s output potential is six times Rwanda’s current peak power usage rate in 2019. A higher ratio applies when calculated for the Kivu provinces in the Eastern DRC. Clean power is just part of the upside. For the region, so too is cheaper power, great export potential and as much as $100 B in 50-year power revenues. This number is before any carbon credits are added.

Rapid economic boost, despite high cost transport fuels

It must be clear that the full development of the Kivu potential has massively positive impacts on the regional economy. Resultant increases in the regional GDP may be higher than 50% from projects completing Kivu’s potential. This potential growth is calculated with minor accounting for secondary growth impacts from cheaper and more available power.

For now we do not include transport fuels in Rwanda’s clean energy future plan. Synthetic gas-to-liquid fuels can be made from biogas, but the capital intensity and durability of hydrocarbon-fueled cars is not so assured. Rather power up battery-driven vehicles for that longer term. EVs remain quite rare in the region, they’re still an expensive luxury. Many vehicles on their roads used to be imported second-hand from Dubai. When Dubai exports used electric vehicles too, they too may become affordable. EVs should work well in the energy mix. Charging them with cheaper, surplus power at night can even out the daily power demand.

Can natural gas production reduce carbon emissions?

Sure it can, although it may seem paradoxical. We read of green activism that rejects natural gas as part of the climate solution, or any clean energy future. The critics classify it as low-carbon but still a climate threat. But in this case they couldn’t be more wrong. The impact of producing Lake Kivu’s biogas applies a sharp twist to that logic.

If we don’t extract gas, the lake will eventually super-saturate with gases and erupt. This means catastrophically. Should it, and depending on when it erupts, the lake can release 2 – 6* gigatons of carbon equivalent in just one day. Therefore the twist of logic is that avoidance of an eruption creates 2 – 6 gigatons of carbon credits to the project. It is a climate winner, in a class of its own. See the graphic for impact relative to other fuel sources’ net carbon impact. Click on the graphic. 1 kWh of Kivu Power fully compensates for the carbon emissions from 5 kWh of coal generation.

We know how to produce this lake’s gas at Hydragas, more safely and productively than anyone else. Our updated solution is fully designed, tested and ready to build. The outcomes are fantastic, high impact, with great benefit to the country. However, we must also be aware what not to do with this potential bonanza. Big problems arise from harvesting its gas the wrong way, or worse still, not harvesting the gas at all.

Staggering numbers for climate impact from using Kivu

Thinking in GHG terms, if Lake Kivu stayed undeveloped it will be a major , one-time, carbon-emission threat. For this baseline case, i.e. do nothing, it will erupt and emit 2 – 6* gigatons of carbon. (* The difference is where one calculates in the range of 25 to 103 tons carbon per ton methane emitted.) That disaster’s probability rises exponentially, but it can happen at any time within the next 70 years. Rising methane content is the trigger. It is also the big climate impact. The USA emits 6-7 gigatons per year, by comparison.

In our proposal, this threat is balanced by going ahead and producing its 60 bcm (billion cubic metre) natural gas inventory and any newly generated gas until the harvesting is done. Then we must use it as discussed here. If done successfully, this avoids and averts 2 – 6 gigatons of carbon emissions. This is a twin impact solution, a positive safety outcome that can also earn the stakeholders huge GHG (carbon) credits for that carbon tonnage.

Clean hydro-power potential

Lake Kivu has been a source of hydro power for more than half a century. However, current use from either hydro and thermal power reaches barely 5 % of its potential. The southern outflow of the lake drops 700m in the 30 km cascade of the Ruzizi River. Studies show a potential of 576 MW from run-of-river hydro. No major dams are needed, so it’s low impact. To date just 30 MW capacity has been installed of the four phases mapped below.

But gas in the lake can also produce thermal power. Of that, only 26 MW is operating. Its potential output, with the best available technology and design in operation, is perhaps 600 MW. This thermal power combined with hydro provides nearly 1200 MW of clean, renewable power.

The Ruzizi River cascade for hydro power

Map of the Ruzizi River cascade below Lake Kivu showing run-of-river hydro projects
Map of the Ruzizi River cascade below Lake Kivu

Three countries will share the future hydro output, as mapped above. After decades of studies and planning, parties signed an accord this week for a consortium to build 147 MW at Ruzizi III. This is another 25% of the river’s potential. The timing is not clear, but would take five years or more. In the meantime, other hydro power projects added 28 MW in Rwanda. 50 MW more hydro power should follow at Rusumo Falls on the Tanzanian border.

Renewable Biogas: part of the clean energy spectrum

What do we know about this added potential from gas energy in the depths of the lake? Lake Kivu is likely the second largest anaerobic bio-digester and store of methane gas on the planet. The biggest remains the oceans. Oceans store biogas and natural gas seeps as solid methane hydrates. They are to date untouched, difficult to recover. But we will modify and build the next generation of our gas extraction technology to produce it after more R&D.

However, Lake Kivu is unique in sealing and storing gas in solution, in deep water. From 250-500 m depths, the gas-in-water solution is rich enough to produce pipeline-quality natural gas. It takes the right extraction and enrichment technology, which is our business. It can produce enough biogas to supply the region’s power. In fact it can make 800 MW of low-carbon power for 50 years or longer. Currently used technologies can do just 15% of that output.

A World Bank accolade for development ideas

The GGFR team in the World Bank has credited our Hydragas team for developing a practical, low-cost model for gas distribution for the 3rd World. We developed this model to use stranded gas in Mozambique in the 1990’s. The country was in a civil war at the time. It was also the world’s poorest country. At the time, the country had stranded gas fields in an isolated area. The World Bank funded some of these Mozambican projects. In fact they really liked and appreciated what they saw in Vilankulo.

The World Bank wanted to replicate and deploy it globally for poorer countries. Their validation assures us that it is also a good solution for Rwanda and the region. For the Vilankulo project we had built the world’s longest plastic gas pipeline at the time. With half of it offshore, it ran some 250 km. It connected two towns and three offshore islands. In fact the gas came from stranded gas supply from the Pande gas field. It had been drilled in the 1960’s but had remained unused 30 years on. We used it to supply the community with much-needed power and pipeline gas at low cost. That system has just passed its 25th anniversary with availability of over 99.9%.

The Vilankulo model from Mozambique

Power generator working on gas in Vilankulo, Mozambique
Power generator working on gas in Vilankulo, Mozambique

The World Bank adopted this “Vilankulo Model”. It became the basis for their gas use model in the Greenhouse Gas Flaring Reduction (GGFR) initiative. In the report, they planned to deploy it in 38 poor countries in three continents. Flared gas would be used to power up local communities. It was planned to provide cooking gas and small power. Gas was previously flared during oil production.

Historic energy shortfalls

Power generation from Lake Kivu has been government priority. But in the 10 years after the 1994 Rwandan genocide, just 10-12 MW of grid power was available in Rwanda. Its government planned a 10-20 times increase to cater for the assessed shortfall. It sought know-how and investment to enable its production, neither of which was available.

Satellite map of the city of Goma north of Lake Kivu, with its 1 million population
Satellite map of the city of Goma north of Lake Kivu,

But even less grid power was available in the DRC’s Kivu provinces from Lake Kivu hydro. For example, the city of Goma in DRC receives just 2 MW for a population of a million people.

Any shortage gets worse because of a seasonal drop in generation. The lake overflow drops in both the long and short dry seasons. Being on the equator, dry seasons occur around the solstices. Therefore both the lake’s outflow and thus run-of-river generation drop.

Rapid change from continuous blackouts to a stable grid

Up to 2006, Rwanda’s power blackouts were everyday experiences. They lasted half the day, in scheduled rolling blackouts. But at the time, less than 6% of the population had access to electrical power. I used to wonder how the rural and even urban population was asleep by 7pm. But lighting was simply too costly to run. An exception was Goma’s bars on the DRC side. Unlike much of Rwanda, Goma came alive at night as the city partied.

To support their lifestyle they use gasoline-fueled generators. These are common for the few connected users and businesses in Goma who can affors lighting. The bars always need light, music and cold beer. It was a shock to see how much mobile phone users in Goma pay vendors for a recharge. Per kW , it’s possibly the highest power tariff extorted anywhere. Only government entities and the well connected enjoyed access to grid power.

Constraints on power supply

Power in the Great Lakes region was and also remains too pricey for most users. It was more than five times higher than say in South Africa or Zambia in 2006. The marginal cost of new power was governed by the cost of diesel generation, with diesel cost very high in the hinterland. Power pricing was a major socio-economic problem for residents and for commerce and industry. Electric power was only affordable to a few, with fixed rates in Rwanda from USc 22-26/kWh. But just 6% of the population had a power connection in 2006.

Today there is much more available power. It is priced at more granular rates by REG-EUCL. It sells at graduated rates for domestic and industrial users. Power connections are up to 51% in 2018. Also, time-of-use tariffs have been introduced for industrial customers with smart metering.

Growing usage is held back by high cost

But pricing pressure continues to severely constrain usage. Low usage is a concern for the utility. Average consumption is just 56 kWh per year for households. This compares to 1800-2000 kWh per year in Botswana and Mauritius. These two are comparably growing economies. Clearly households shave usage to a bare minimum, typically for lighting and electronics only. Charcoal and firewood are the costly, but most economic choice for heating and cooking.

In the DRC, regulated domestic power tariffs are far lower than industrial rates. However, DRC’s utility SNEL, has severely limited power supply to Goma. Just 2 MW of grid supply serves a city of a million people. This is less than typical city blocks use in developed countries. Domestic users received no supply despite paying a connection fee. Comment on pricing is a moot issue in a no-supply circumstance. If SNEL restores supply to more users, pricing must respond to markets rather than distorted regulation.

A clean energy future needs smart solutions

Hydragas studied and modelled energy supply needs of Rwanda and DRC as part of our gas production studies. We prepared feasibility assessments on energy competitiveness and market size. The market was price sensitive. Our recommended fix was to supply combined power and gas feeds into households. Power alone could not satisfy the needs affordably.

The connected customers would preferably use it for essential lighting and electronics. Charcoal is preferred for cooking. But the poorer rural users consume only firewood and no power. Gas, once distributed to homes, can supply the bulk of energy needs in almost all homes. Combined gas and power can be supplied more cheaply and effectively than its alternatives. But the utilities are faced with the cost of connecting two energy sources.

Several sources can contribute to the power supply mix for Rwanda. This mix includes hydro, biomass (peat) thermal, solar PV and thermal power from Kivu’s renewable gas. Wind and solar are seasonally less effective than in other parts of Africa, with low power factors for 7-8 months a year. It’s partly due to few months of sustained winds and short sunny seasons.

Balancing thermal energy and electrical power

But for the country’s generation fleet, it should look to retire its hired diesel generation fleet first. It has been its generation mainstay, but the cost is higher than the retail pricing. To achieve 100% clean energy, the utility can re-deploy HFO thermal units as stand-by or for peaking power. Kivu gas-to-power can supply the base-load demand, reliably and cost-effectively. With further capacity, this source can later supply export grid power through the East African Power Pool. This is a pathway to expanding the region’s clean energy future.

Kivu gas can and should supply thermal energy. Better still, use renewable natural gas or RNG for this purpose. It is a cheap and convenient heat energy for households and industry. A key impact from gas use is to halt or reverse deforestation.

Cooking on RNG to reduce deforestation
How renewable natural gas replaces biomass

A capital investment need is a new national gas network. This will provide the backbone for gas transmission and distribution around the country. The geography of Rwanda is perfect for running a cost-effective HDPE gas supply network. A medium-pressure network is an expanded form of the Vilankulo concept. It works because Rwanda is small and the most densely populated country in Africa. This therefore reduces the capital cost per user. We advocate the Vilankulo concept, compatible with newer US and EU-based design standard for pipelines.

A simple commercial model for our times

We prepared feasibility reports in the 1990’s for Mozambique’s local gas and power distribution. To cut costs to users, we made it simple and cheap to operate in rural Africa. The donors funding the scheme, from Scandinavia, had a Norwegian expert review our town supply study.

To our amusement, the queries he raised included the following: Why no fleet of vehicles for the utility staff? What was the budget for an office block, or for a proper computer billing and administration system? Where is the workshop to repair all the gas meters and test or calibrate them? Also, where are the trench-diggers and earth-moving equipment? This is a very euro-centric or North American view. His list would have more than quadrupled the project cost and made gas unaffordable. But in Vilankulo, a man on a bicycle could carry most needs for a house installation and he could install it in an hour.

Simple lessons from Nigeria on commercial strategy

This was where EU standard household installations were too expensive. Our gas project team was looking at how to cut out costs in Mozambique. Here revenues would take five years or more to pay off installation costs. We found that half the capital cost was metering. Why even install a gas meter that costs 5 years gas usage? It will never pay back. Why specify the legacy household gas fitting to be the same as Europe? In Africa, the cost of that household gas installation will exceed the cost of the house itself.

Our commercial pricing model originated in Nigeria, in power metering. A trip to Lagos at the time gave us a clue. Apartment landlords had addressed the same problem with electrical usage. Instead of a meter per apartment, they inspected each tenants connections. A light bulb was one point, a stove 15 points, a fan five points etc. Each tenant’s total was divided into the apartment’s and multiplied by the total bill. It worked for everyone. Indeed it was widely accepted as fair and runs in most cities there. Because of how logically it works, any cheating both hurts and is visible to one’s neighbours.

Delivering the clean energy future, sustainably

This post starts with high ideals and the grand plan for a clean energy future in Rwanda and Eastern DRC. They make a difference at country-scale. The concepts on how this is set up are also explained. So I have dived into the detail to explain some of the simpler concepts to roll out clean energy, especially for gas distribution. These are real, and have gone live.

The plan’s methods have been adopted by the World Bank as their best practical example for the GGFR initiative. This flaring reduction initiative was a plan to implement in 38 poorer countries with stranded gas. In fact the plan is to make the operation of gas supply and even power supply cheaper to poorer users. These methods are also simple for small communities to implement with entry-level contractors and businesses. There is no need for multi-national utilities to be part of the solution.

Legacy utility systems are less needed. Also, commerce is simplified by using cellphone apps to manage billing and management. East Africa already leads the world in adoption of mobile systems for banking and payments. These approaches go some way to making energy more affordable, cleaner and more sustainable.

Finally

The leader of the Sabyinho gorilla family group in the Virunga mountains in 2003
The Leader of the Sabyinho Family in the Virunga Mountains

P.S. I noted on the cover photo to this post the image of a “Big Gorilla” formed by the cloud. The photo is one of mine of Lake Kivu. It is over ten years old. I was staring at it, thinking of how this is the land of the mountain gorillas when I saw it. The volcano is 14,000 feet high, and the imagined “gorilla” must be 25,000 feet or more. It is an icon of the region and I hope it means well. 🙂