We're excited to present PV-Pix, the result of a collaboration between material science,
design, and engineering researchers as well as slum community co-designers. PV-Pix are
a novel computer-mediated form of inter-family expression using interactive and self-sustaining
photovoltaic material. Using PV-Pix a person in one household can create a pictographic
message, such as a reminder to bring an umbrella, which is subsequently displayed in another,
connected household.
PV-Pix are inspired by advances in material science that have created exciting new 'computational
materials'. Materials that can harvest sufficient energy from the environment to carry out functions,
such as sensing, actuating, as well as storing and communicating information.
We wanted to explore the forms and functions such materials might take on outside of the
research centres in which they are typically developed. In our case this was with emergent
users in Dharavi, one of Asia's largest slums located in Mumbai, India.
Dharavi has around a million residents who are culturally and linguistically diverse.
They have varying levels of textual and media literacy. This is why they are sometimes referred
to as 'emergent users'. That is people, who are just getting their hands on advanced digital
technologies, such as the mobile phone, but aren’t necessarily able to access all functions.
Before the pandemic we conducted co-design workshops with community members. Participants
recognized the value of self-powered devices because there are only few electrical outlets
inside a typical Dharavi home. They also valued connecting friends and family. To further
investigate how computational materials can be embedded into fabrics and surfaces of a
Dharavi home, we organised a follow-up diary study.
Because of the pandemic, this study was conducted remotely using WhatsApp. Over the course of
a week, study participants showed how they arranged and rearranged their home depending
on people and activities over the course of a week. Together with residents we identified
windows and room-dividing curtains as promising places.
To give participants a sense of interactive possibilities that could be driven with small
amounts of energy harvested from these windows and curtains, we created a low-fidelity prototype
that we deployed with participants in Dharavi over 4 weeks. Here’s what they looked like.
Encouraged by the creative and meaningful messages that participant families shared
with each other during the study, we took first steps to engineer technical prototypes.
To implement these, we chose dye-sensitised solar cells or DSSCs because of their low-light
performance, aesthetics, and low manufacturing costs.
Compared to other photovoltaic materials, DSSCs can generate enough energy from indirect
light to drive low-power actuators and communication radios.
DSSCs are dye-sensitized and semi-transparent. We utilised these properties to give PV-Pix
a pleasing aesthetic dimension.
And finally DSSCs are comparatively low-cost and easy to manufacture: opening up exciting
possibilities of local manufacture and customisation.
Moving forward, we provide a toolkit to accompany this paper in order that other researchers
can join us on this research journey.
And looking back, we would like to thank the co-designers, participants, facilitators,
and funding agencies who enabled this research.