©2019 by UNIT 17, The Bartlett School of Architecture, UCL

Grace Liberty Fletcher

gracefletcher@gmail.com

A proposal to regenerate the abandoned island of Stroma through the surrounding sea water and tidal energy of the Pentland Firth. The project attempts to encapsulate the perpetual dissonance between entropy and preservation: to balance control on the edge of chaos. The driving inspiration is the theory of Secondary Endosymbiosis, whereby one eukaryotic cell engulfs another, creating organelles such as mitochondria and chloroplasts.

For me, this phenomena
is so radical because it marks the genesis of an autonomous cell: a closed, self-reliant environment. Research, in particular into the Siegfried Ebeling’s text ‘Cell as Membrane’, describes a potential for energy self-sufficiency in houses. Ebeling looks to the membrane that separates ‘inside’ from the external environment, as the place where
energy should be harvested.


My early research stemmed from an interest in entropy and architecture. The theory of entropy as the arrow of time: the notion that substances continue to move from states of order to disorder, yet within this, architects try to harness a localised area of order.

I wanted to challenge how design and intention can coexist with the inevitable forces of our environment.The Pentland Firth is a body of water that separates Orkney from Scotland. It has some of the fastest
tidal speeds in the world, which has sparked huge investments in order to harvest the renewable resource. The island of Stroma lies in the tidal stream, and it has an innovative relationship with the Firth. The powerful tides would fly over the flat island forming pools, which locals used to drive tidal mills, and records from the 16th century remember cliff edge mausoleums where the dead were mummified by the intensely salty air.

I set myself the task to see how I could regenerate the island of Stroma through the tidal energy that surrounds it. I identified the most crucial step would be to store the energy, which led to the proposal of converting the dilapidated crofts around the island into salt water batteries. The crofts would be connected into local networks and the historic reservoirs reinstated to harvest brine.The island has a dichotomous condition whereby the east is dry and fertile and the west is inhospitable and salty.

I was interested in the place where these sides meet: the concept of an ecotone describes this transitional area as a place of enhanced biological and geological richness. In response, a permeable membrane is constructed along the divide to enhance the existing potential difference, in turn setting up the entire
island as a salt water battery. The membrane also acts as an electric spine, which docs the tidal energy and connects
it up to the croft network.


The battery accumulates in the centre of the island, with a power station built of salt and gypsum residue. The materials are the products of the reduction of salt water and this resource that the building is born from is what it will eventually break back down into. 

The form is developed from the structural and physical qualities of stalactitic gypsum
and crystalline salt: respectively smooth and matt, and rough, luminous and glittering. Material testing developed a method whereby the two materials are cast into each other, creating a hybrid. As well as raw material production the building functions as a substation, where electricity is transformed and regulated in order to be stored or transferred.
There is an ambition to challenge the typical built form of 21st century electricity systems. Typically, the design
ambition is to hide and camouflage infrastructure, appearing in denial of a function that our society relies on. Stroma
Salt Station is designed as a beacon that celebrates the invisible phenomena that our culture is built fromw.