The Lake That Generates Power

In the transition to low-carbon energy, Bulgaria can rely on investors with solid experience and knowledge

The plans for achieving full carbon neutrality of the European Union and the need for serious changes in the energy sector of Bulgaria continue to be at the center of news and on the public agenda. The issue is particularly sensitive against the backdrop of high energy prices across Europe, and for ordinary citizens green transition is more and more a source of concern and uncertainty for the future. In the coldest days of January, nearly 60% of the country’s electricity was from the coal-fired power plants, and in view of European climate policies there is already a timespan on their work.

These capacities, in addition to guaranteeing the country’s energy security, are also a serious economic factor of regional and national importance, providing livelihoods for tens of thousands of families. Therefore, it is hardly a surprise to anyone that people from the affected regions do not stop worrying about what will happen to their lives in the post-coal period.

At the moment, the indicative date for phasing out all coal capacities in the country is still 2038. The institutions are still working on scenarios for the future of Bulgaria’s energy sector, and difficult decisions are yet to come. It is clear, however, that the energy transition will require over a billion BGN of capital investment annually, which far exceeds the limited public resources and attracting investors will be extremely important. The good news is that in the Bulgarian energy sector there are already investors that the country can count on during the transition and in the period after, because they have the necessary experience and know-how in different energy projects, and have proven to be responsible employers, exact taxpayers and good business managers.

Such an investor is the global energy company ContourGlobal, the majority owner of one of the two modern coal-fired power plants near Stara Zagora – ContourGlobal Maritsa East 3 TPP. In 2021, the plant, which employs nearly 500 highly qualified specialists, produced electricity for almost half of Bulgarian households. During the years of modernization and beyond, more than BGN 1.4 billion have been invested in ContourGlobal Maritsa East 3 TPP, ensuring its reliable operation in compliance with the highest European standards for safety and environmental protection. Over BGN 10 million have been invested in improving the quality of life of local communities in the Stara Zagora region and especially in the town of Galabovo and the surrounding villages, where the plant is located.

In addition to the power plant in Bulgaria, ContourGlobal manages 138 energy projects in 20 countries on 4 continents. These more than 6 300 megawatts of installed capacity use many different sources for power generation – such as lignite coal, natural gas, diesel as well as renewables – photovoltaic plants in Italy and Slovakia, concentrated solar power plants in Spain, wind farms in Austria, Brazil and Peru, hydroelectric power plants in Armenia. Some of the company’s projects have long relied on an innovative approach in developing a successful strategy – both environmentally friendly and effective for consumers and businesses. One of ContourGlobal’s most interesting projects is in Lake Kivu, Africa, where the company generates power from biogas.

Located on the Democratic Republic of the Congo – Rwanda border line, the lake is one of the largest in Africa and the ninth deepest in the world. It is also one of the most dangerous. At the bottom of Lake Kivu, there is enough gas to power Rwanda for the next 50 years … or potentially poison the thousands of people living in the area.

‘Carbon dioxide enters the lake from the surrounding volcanoes through the volcanic rock at the bottom of Kivu, where bacteria turn part of it into methane,’ explains engineer Atanas Deyanov of the company’s young international team. ‘In ordinary lakes, this gas would disperse slowly into the atmosphere, but in Kivu it is hindered – there is a layer of water above it, rich in minerals and high density, and all the gas remains under pressure at the bottom. Scientists believe that every 1000 years there is an eruption of harmful gases, which can be deadly.’

ContourGlobal sees untapped opportunities in the dangerous nature of the lake. The company launched the KivuWatt project, an integrated methane extraction and production facility and a 25-MW power plant, commissioned in late 2015. Methane is extracted from a 350-meter barge located 13 km into the lake. The plant’s pumps draw gas-saturated water from the bottom. When it comes to the surface, water and gas separate naturally. The resulting gas, with a methane concentration of about 20%, undergoes a process of separation of carbon dioxide from methane. In order not to disturb the delicate balance in Kivu’s waters, the purified water and much of the carbon dioxide are returned to the lake, and the already methane-rich gas is transported by pipeline to the onshore power plant and used to generate electricity. ‘The process is like opening a soda bottle – by reducing the concentration of gas, the lake actually becomes safer. In addition, thanks to KivuWatt, people living in the area now have normal power supply’, said Eng. Deyanov.

It is believed that if the gases at the bottom of the Kivu are not extracted, they would accumulate reaching a threshold and erupt, especially in the case of significant volcanic or seismic activity. Apart from Kivu, there are only two other similar ‘exploding lakes’ in the world – Nyos and Monoun in Cameroon. In 1986, a landslide in Lake Nyos caused a gas eruption and in just minutes suffocated 1700 people and 3500 animals within a radius of 25 km. Unlike the two lakes in Cameroon, which are located in sparsely populated rural areas, Lake Kivu is much larger and is home to more than two million people.

The KivuWatt project is unique worldwide and currently covers nearly 30% of Rwanda’s annual electricity consumption. Secure and affordable electricity comes with even more attractive achievements – with the commissioning of KivuWatt, Rwanda’s energy sector carbon emissions have been reduced by 44%. ContourGlobal is considering increasing the facility’s capacity to 100 MW, providing the electricity needed to develop this part of Africa. Scientists believe that KivuWatt alone will take years to reduce the methane accumulated at the bottom of Lake Kivu to safe levels. But the project is a step in the right direction and this is recognized by the international community – the company was awarded the 2011 Africa Power Deal of the Year by Euromoney’s Project Finance magazine award.

ContourGlobal’s experience in developing innovative projects can undoubtedly be useful in the energy transition in our country as well. Decisions are to be made for the development of the Bulgarian energy sector, which should be in line with both the climate goals and the energy security and the availability of affordable energy for all consumers. Bulgaria is in a good position with its potential for new capacities from renewable sources and its existing base capacities, including in the Maritsa East complex, for the implementation of a smooth and predictable transition. The proven capabilities of international investors and the excellent expertise of local professionals and a highly qualified international team, combined with favorable predictable conditions to be created in active cooperation with institutions, are the right recipe for sustainable development of the entire energy sector.