Malawi Geothermal 2017

De-Risking the Geothermal Resource of Malawi

Earlier this year Dr Tim Raub, David Townsend (an ex-student and Founder of Townrock Energy) and myself made a reconnaissance field trip to Malawi to assess its geothermal potential.  We were joined in the field by ex-St Andy and lecturer in Geology at Chancellor College, Malawi, Dr Blackwell Manda. The trip covered the length and breadth of the country and finished with the delivery of a workshop on geothermal to university, government and industry. 

David Townsend and Blackwell Manda at the 

The project has grown out of our Department’s interests in geothermal in Scotland and abroad. It also continues a focus we have had on East Africa over the last 10years specifically with work in Ethiopia. 

So what geothermal interests do Africa and Scotland have in common you might well ask? Well both countries have a growing need for off-grid and end-of-grid energy solutions and both have some geothermal potential.

Global Challenge

The ubiquitous provision of clean, reliable energy represents one of our key Global Challenges that has both economic and well-being impacts throughout the developing world.  In so many countries, the current status where both heat and electrical power are supplied via erratic systems severely impacts economic growth.  In addition, the use of carbon-based (often charcoal) cooking systems has crippling health impacts, with associated deforestation causing further compounding of local environmental damage.

Over the last 10 years many developing nations have leap-frogged the Western world in telecom technology with a step change in thinking that is revolutionising daily lives (GSMA – The Mobile Economy, Africa, 2016).  In a similar mode, energy provision could also make a step change by not following a typical delivery system for energy through grid supply.  Rather, an off-grid model of energy provision (supply and storage) based on a scalable solution for small homesteads, through villages to townships could offer not only vital power to stimulate local industrial growth but could do so with major health benefits for the local populations. Furthermore, providing independence in energy at a local level would also address many of the issues caused by rural depopulation to cities and if the power is supplied by renewable, low to zero carbon means this would have wider global impact.

use of geothermal spring for washing

Addressing rural energy needs in the past have often failed as they have attempted to provide a singular energy solution to all settings.  Rather, the diversity of rural settings necessitates a flexible approach that offers a varied range of scalable solutions working together in an integrated network. Different physical settings require different combinations of technology. Renewable systems such as biomass, geothermal, solar, wind and hydro could provide the required mix of both electrical and heat base load together with peak demand when properly managed and backed-up with appropriate storage solutions.  The implementation of these solutions will require specialist teams of experts including resource scientist, engineers and social scientists. 

Malawi's needs

new pit being dug for using geothermal water for fish farming

Currently, Malawi produces 99.7% of electricity from hydro-power.  Supply cannot meet demand, and blackouts are regular in urbanising areas and normal in rural regions.  Most of the ~18 million population lives and works off-grid.  Assuring an energy future through carbon-based resources or nuclear comes with a price.  Further, as biomass burning is ubiquitous at a local level, this has large impacts on the environment and in particular the many unique forest ecosystems.  Biomass burning also contributes to soil erosion and hydro-power dam siltation, exacerbating Malawi’s energy crisis.

These power- and heat-generating challenges stunt development of industry, discourage tourism, frustrate personal ambition, and degrade Malawi’s cultural heritage. 

Solutions however are available.

Our initial funding from Global Impact and EPSRC funds allowed us to undertake an evaluation that consisted of three parts:

•        Background desk-top review of geothermal potential including heat analysis of the country-wide geological database and recently acquired airborne geophysical survey

•        Reconnaissance survey of known hot-spring sites

•        Delivery of preliminary results plus geothermal methodologies and economics at a workshop to local stakeholders

Calculated heat production map and geothermal centres

Recommendations - a collaborative approach

stakeholder meeting 

It has been clear from the activities during Stage 1 of this project that there is not only a national geothermal resource for development in Malawi but that there is an appetite for development at both Government level and most importantly at a local level.  The latter is manifest by the high level of local interest we found during our field visit especially from young entrepreneurs.  They are clearly an important part of future developments as it is through local development that communities will benefit most. A course of action for us now includes the following:

Stage 2

•        Later this year we will be hosting a visit by a team of Malawian engineers.  The visit will include meetings with Scotland-Malawi Partnership in Edinburgh; with collaborators at Strathclyde University in Glasgow; with industrial partners SASOL in St Andrews and ARUP in Edinburgh. A visit to the Netherlands geothermal operational plant is also planned

•        Further field tests will be conducted at a few of the already visited sites in Malawi to better determine the resource potential.

•        Working with socio-economic staff from University of Malawi an assessment of the social infrastructure for development and level of local (entrepreneurial) capacity for development will be made

Stage 3 – longer term plans will then include:

•        Drill to test the geothermal potential with two, 100m boreholes (testing the geothermal gradient and flow rates)

•        Build energy and resource development partnerships – these will include key players both in Scotland and Malawi at academic institutes, government bodies and private companies 

•        Delivery of integrated system to two test sites.

Orkney 2017

Orkney 2017

This summer we (the Rising Tides team – Caroline Wickham-Jones, Martin Bates and Sue Dawson) undertook a number of field trips in Orkney to cover a growing number of projects with partners at the University of Highlands and Islands.

Bay of Ireland

Moving south from our work in the loch of Stenness we have begun a collaboration with Scott Timpany at UHI, Jane Bunting at Hull University and Michelle Farrell at Coventry University. This project aims to contextualise the findings that UHI have published on around the peat deposits where a large oak timber was discovered by Ted Pollard during a campaign of coastal walking (Timpany et al., 2017).  The Bay of Ireland opens into Scapa Flow, the infamous site of the scuttled German battle fleet from WWII. Our investigations however focus not on this rather on the very much older landscape during the early Neolithic when sealevel was still rising to that of today. This now submerged area is typical in that it has an infilling of both ancient and modern sediments.  Our first task was to map these and determine the depth to basement (rock and glacial till).  As with previous geophysical investigations it was also hoped that we might be able to see different layering within the sediments to discriminate packages that could be associated with different environmental conditions. We used the UHI Geoacoustic pinger for the initial survey.  Results gave us the required depth to basement but the quality of data was not sufficient to image sediment packages.  As can be seen by the map of basement depth the bay takes the form of a buried basin that deepens to the south.  

Map of depth to basement and example of sub-bottom profile, Bay of Ireland, Orkney 

The southern limit of the basin is marked by a submerged bank or barrier that stretches roughly east-west across the bay and separates it from the main part of Scapa Flow. Armed with this data we attempted to core through a thicker part of the sequence in the centre of the bay. The core penetrated over 2m of sediment that we now need to analyse.

At the same time as the marine work Scott also attempted to follow the peat layers offshore from the landside.  A rather gloomy, wet day saw him joined by Martin and Sue with hand augers. 

Diving

Following the geophysics and coring we were fortunate to be joined by Nat Hirst and Kerry Santander from SeasearchScotland.  Seasearch divers usually scour the bottom looking at biology but they were game for trying their hand at underwater archaeology in the form of hunt the peat!  Before diving Scott primed them on what sort of features we were after and we armed them with core tubes that could be inserted (bashed with a lump hammer!) into the seafloor.  Over the course of two days they dropped on a number of sites both here and in the Bay of Firth adding greatly to our understanding of the conditions.  Tough work but with the good weather a rewarding trip.  Hopefully they can be encouraged to return when we have more sites for diving.

hand coring on seafloor

Skaill and Skara Brae

In September we returned to the loch of Skaill as our previous attempts to core this site had been thwarted by strong winds. The objectives of this investigation are aimed at further understanding the role of coastal barriers in protecting heritage sites.  In particular we are trying to not only reconstruct the past environments around iconic settlements like Skara Brae but also to understand how the environment changed, and over what time periods it changed.  Once again, the changes are not only linked to climate fluctuations but also to sealevel rise.  It is likely that Skara Brae was first located some distance from the coast with a wetland between it and the sea. As the sea rose the coastal barrier was breeched and the land was flooded. Over the ensuing millennia the sea gradually eroded evidence for this land surface however the environmental conditions are still preserved beneath the site and in the surrounding landscape.  For example, during coastal protection work at the site in 2009 a significant peat layer was noted at the base of the revetment scheme.  Unfortunately, the works did not record this or sample for further environmental signatures.  Published work by de la Vega et al in 2000 does provide a broad environmental setting for the site however our investigation aims to put far more detail into the story. 

A series of cores both on the wetlands to the south of the site and in the loch of Skaill were taken and show a complex sequence of sand, peat and loch sediments. There will certainly be enough in here for environmental analysis over this winter.  Based on these results it is intended to return to the site with a range of environmental geophysical techniques in 2018.

Orkney International Science Festival

September also features Orkney International Science Festival, an event that we try to participate in on an annual basis.  This year we managed a great afternoon out with the P6 class at Dounby Primary School at loch of Skaill, a coring of the Peedie Sea with Scott Timpany at UHI as part of their project on Medieval Kirkwall, a joint exhibit of our palaeo-environmental reconstruction at the family day and a talk on the Borth fossil forest by Bates, Bates and Bates!! (my father, Denis and brother Martin giving the low down on joint work in mid-Wales).