IS IT REALLY RENEWABLE, FOR PEAT’S SAKE?

I’m re-posting this blog with permission from the University of St Andrews’ Energy Ethics group, for whom I wrote this piece.

As part of Energy Ethics 2020, I joined three other panellists on Friday 13th November to debate the question: Are renewable energy technologies a sustainable solution for meeting the world’s growing energy needs? It was a fascinating 90 minutes, filled with interesting and shocking facts about the dimensions of renewable energy in the 21st Century. I learnt that if we wanted to rely on biofuels, we would have to plant crops on the whole of the world’s terrestrial surface in order to replace the 15 Empire State Buildings’ worth of crude oil that is currently extracted per day; that an average electric car uses three times more copper than a conventional car (where does this come from!?); and that many people in the Majority World lack access to sufficient energy to light up their homes for educational purposes or to cook without subjecting the household to air pollution, let alone have access to renewable energy sources. The challenges of powering the world on renewable technologies were as palpable as the need to overcome them in order to reduce our reliance on fossil fuels; and reducing this reliance is imperative if we are to limit the impacts of ongoing climate change.

I am an ecologist, who has studied landscapes in which bio-energy production has been one option for land use. Since energy use and sourcing is a topic that touches all of our lives, I have spent some time thinking about how we might produce renewable energy whilst ensuring we uphold the environmental pillar of sustainable practice. I remember being excited by palm oil, touted as the great solution to diesel-fuelled transport. After millions of hectares of Southeast Asia were converted into oil palm plantations, the critiques started to roll in: we are taking up precious agricultural land to fill our cars with biofuels whilst people starve; we are destroying miles upon miles of biodiverse tropical forest to plant a monoculture that provides limited habitat for wildlife; we are creating huge carbon emissions in the process of growing this ‘renewable’ fuel, amongst other condemnations. I remember getting excited about Jatropha, claimed to be a more renewable alternative, as a biomass crop that could be grown in areas that were already ecologically degraded. But Jatropha did not prove the golden ticket either: the crop requires significant inputs of fertilisers, pesticides and water (through irrigation systems) in order to be productive, and the process of converting Jatropha seed oil into biodiesel results in large greenhouse gas (GHG) emissions itself. There are large questions around the sustainability of these two biofuels (and many others). There is also enquiry to be made around whether they are actually truly ’renewable’.

A commercial plantation in Sarawak, Malaysian Borneo, where the oil palm, Elaeis guineensis, is grown to produce palm oil. [Photo credit: Lydia Cole]

According to Oxford’s online Lexico, a renewable resource is defined as one that is “not depleted by use”. The resource therefore has to regenerate at the same rate that it is harvested or otherwise consumed. For example, sufficient time must be left between the logging rotations in a tree plantation to ensure that the trees grow to reproductive age before they are harvested. If trees are harvested too early in their growth cycle for natural regeneration to take place, a key dimension of the renewability of the resource is undermined, along with the interdependent system in which it grows: the soil, with its finite stock of nutrients and growing material; the water supply to ecosystem; and the diversity of plants and animals involved in nutrient cycling and natural regeneration. If the context and condition of the whole ecosystem is considered, as the fundamental housing from which renewable resources are produced, many of our current ‘renewable’ resources would be axed from the list.

An area of deforested peatland in Sarawak, Malaysian Borneo, in the process of being converted into an oil palm plantation. [Photo credit: Lydia Cole]

One resource that epitomises this renewability challenge is peat. Peat accumulates at an average rate of one millimetre per year, in waterlogged environments where the lack of oxygen slows down or entirely halts the process of decomposition. Burning one cubic meter of extracted peat is the equivalent to releasing one thousand years of accumulated carbon. It is produced through the natural process of harnessing the sun’s energy via photosynthesis, the same process as produces wood-fuel, but the slow regeneration time of peat demands that if we burn it, we must do so at an impractically slow rate.

Aside from the extensive time required to re-accumulate the equivalent carbon belowground that is extracted when peat is harvested, the process of extraction itself often leads to large carbon emissions. The equipment deployed uses fossil fuelled combustion engines and emits CO2, but even greater volumes of GHGs result from the disruption of the waterlogged environment, which is an inevitable part of the extraction process. This prevents the ongoing ‘sinking’ of CO2 from the atmosphere into the peat substrate. It also results in the release of carbon that was previously inaccessible to the forces of decomposition, which cycles the plant-derived organic carbon back into the atmospheric gas that we have come to dread. Rwanda, a country striving for domestic energy security and energy accessibility for all, has recently built a peat-fired power station. International financing and engineering assistance, primarily from Finland, has supported the development of this “sustainable electricity” infrastructure. But this strategy of burning peat for electricity generation is far from sustainable, and even further from a system harnessing a renewable resource, as I have touched on here.

Rwanda’s first peat-fired power plant at Gishoma. [Photo credit: Rwanda Energy Group/Twitter]

Though the balancing of the three pillars of environment, society and economics to develop sustainable solutions to meet our energy needs is no trivial task, a sufficient understanding and consideration of the environment component is essential if the other two pillars are not to be undermined. But when has any big transition occurred without challenge? And it is challenge that drives innovation and positive change. To end the discussion, the panellists were asked for their final (ideally positive!) reflections in order to provide food for thought moving forward. Building decentralised, appropriate renewable energy systems at a community level was mentioned by several of us. One panellist emphasised the need to create macro-policies with micro-foundations. He also reflected on the need for a dimension of international cooperation and support, through knowledge transfer and financial assistance, to lend the opportunities of renewable energy to those countries less able to develop their own. Promisingly, finding the money for these initiatives now seems more possible than ever, with recent COVID-19 related budget decisions demonstrating to the population here in the UK that our national Government can deliver when it chooses to. There was further optimism in the recent election of a new leader in the United States of America, Joe Biden, who has both acknowledged the reality of climate change and will likely choose to provide national and international leadership on approaches to solve this challenge. But we were reminded, as conscious citizens, that we must hold our leaders to account and show them that we are willing to embrace equitable and truly sustainable solutions to one of the greatest challenges of our age.

Fare forward, women.

I’ve just been included in this article, written to celebrate International Women’s Day: Ten BES women you should know about. Probably a networking-related turn of events that meant I was on the author’s mind, but I thank her very much for including me. “They” always says this…but it really is an honour to be on this list with those other babes. I will endeavour to keep putting my energy into things that I believe are important – engaging people in ecology and conservation, building the confidence and vision of individuals and nurturing kind communities.

And here’s a poem for these times that a hugely inspiring female friend sent me:

Image

 

Power from peat in Rwanda

Last week, an article that I showcased on my blog a few months ago was published (re-vamped) in The Conversation.  Since it went live, I’ve had some very interesting comments and conversations about where and how we get our electricity.  What is the best source of power for a country?  What factors are considered in making that choice?  Which takes precedence over energy-efficiency, cost-effectiveness and environmental impact?  Is the latter even considered?  I am beginning to understand the complexity of issues involved in making choices between fossil fuels, renewables, national and international energy supplies, access and development.  But I have much still to learn.  It’s perhaps the biggest challenge of our time.  Whatever the answer though, power from peat is surely not a solution.

Rwanda adds to energy mix with first peat-fired power plant in Africa

Image 20170406 6397 rtc6o3
Rwanda’s first peat-fired power plant at Gishoma is currently running at 10.85MW.
Rwanda Energy Group/Twitter

Lydia Cole, University of Oxford

Rwanda recently celebrated the opening of its first peat-fired power plant at Gishoma in the far west of the country, a $39.2M project. It is the first of its kind in Africa. The Conversation

Another larger peat plant, costing $350M is under development in Gisagara to the east. The plan is for Gishoma to start feeding 15MW of electricity into the national grid imminently, and Gisagara 80MW by 2019.

The Rwandan government is hoping to achieve its goal of connecting 70% of the country’s 11.7 million people to the national grid by 2018. This is a near three-fold increase on the number connected at present. The peat-to-power plant at Gishoma will contribute to this goal, and further increase the installed capacity of the nation. This will reduce Rwanda’s reliance on expensive imports of diesel oil for power generation.

At the moment, only 25% of households have access to the 190MW of power generated in country. But over the next two years the capacity is projected to reach 563MW in line with national development goals. This increase will be made possible in part through the harnessing of power from peat.

Peat power

Peat provides an effective energy source when dried, comprising a minimum of 30% organic matter. It develops under anaerobic conditions, where waterlogging significantly slows or prevents the decomposition of dead vegetation. As the vegetation grows in the surface layers, it absorbs atmospheric carbon through the process of photosynthesis. When it dies, this carbon is stored in the accumulating substrate which is peat.

Peatlands are found across the world. But they are concentrated within certain regions where high humidity or low temperatures reduce the rate of decomposition. These include the coastal lowlands of southeast Asia or northern Russia’s permafrost zones. Despite covering just 3% of the world’s ice-free land surface, peatlands store up to 30% of its total soil carbon stock. This makes them the most efficient carbon storage facility we have.

But arguably, not a renewable one. Though each peatland varies, one centimetre depth of peat may take an average of 10 years to accumulate, and less than 10 minutes to burn.

Rwanda energy mix

Rwanda’s energy comes from a diverse mix of renewable sources. Hydro-power is the main contributor at 59%, followed by thermal (40%) and methane (1%). There are also ambitious plans for off-grid power from solar.

Peat power is considered one of these more sustainable indigenous sources of energy. It has the potential to contribute nearly 20% to the national energy supply in five years’ time.

The Gishoma plant is nestled within the Nyungwe Forest National Park.
Shutterstock

It’s estimated that there will be sufficient peat deposits to power Rwanda for 30 years, or some proportion of the country at least. The enhanced power that will come from the Gishoma and Gisagara peat-to-power plants is seen as an important part of the country’s development provision.

The plans are enabled through financial support from the African Finance Corporation, the Development Bank of Rwanda and Finnfund, the Finnish Development Finance Company, among other lenders. Finland has expertise in peat extraction and its use in the energy industry, with an average of 5% of its national supply coming from peat. This was encouraged by subsidies until recently.

But where is Rwanda’s peat?

The Gishoma plant is nestled within the Nyungwe Forest National Park. This is an

untouched natural rainforest that is filled with exciting biodiversity.

The park’s website boasts of the presence of hundreds of species of trees and orchids within the park, such as the swamp-dwelling Eulophia horsfellii. It’s also host to numerous plants species of medicinal value, like the East African satinwood, Zanthoxylum gilletii, and to one of the last stable populations of chimpanzees in East Africa. But there is no mention of peat. It’s evidently not a key feature for the average tourist.

There are vast areas of peatlands across the Tropics that we are only now starting to map and understand their full extent and carbon content. For example, it was only a few months ago that the first map of the world’s largest tropical peat complex was published. Around 145,500 square kms of peat swamp forest was found in the central Congo Basin.

There may well be vast resources of peat in Rwanda that local residents have known about for years, or that the Finns have sniffed out recently, of which science has yet to be told or be concerned about. But whatever the scenario defining the nation’s peaty asset and wherever it is exactly, it is unlikely to be there for much longer if peat-to-power generation continues to be Rwanda’s cost competitive energy solution.

Given that it takes thousands of years to accumulate just hundreds of centimetres of peat, is peat-power really the solution to the nation’s energy needs? Can the Elon Musk’s out there create an energy-storage solution quickly enough that renewables make a serious contribution?

For now though, Rwanda is set to power through its peat.

Lydia Cole, Researcher Associate of the Department of Zoology; Environmental Scientist, Rezatec Ltd., University of Oxford

This article was originally published on The Conversation. Read the original article.