ShareCart
ShareCart is a shared ordering system that connects households to buy bulk from producers at lower prices, letting each household only take what they need to minimise excess food waste. It is designed to help small households access bulk-purchase prices without overbuying, waste, and complicated logistics. By pooling orders with others nearby, users only buy what they need - reducing cost-driven overconsumption and preventing food waste. This project was completed over 12 weeks as a team of five on our chosen brief on food-waste reduction.
Project Overview
Full Research
Document
This document shows the evolution of our concept from early sketches to refined design decisions, illustrating how evidence shaped each iteration. It offers a comprehensive view of how ShareCart responds to user needs, logistical constraints, and broader sustainability challenges.
Problem Domain
Australia wastes 7.6 million tonnes of food each year, costing $36.6 billion and generating 3% of national greenhouse emissions. For our project we wanted to examine this problem within the domain of food waste management in urban environments, specifically Melbourne. This choice was driven by the significant environmental and socioeconomic effects of food waste, specifically its role in greenhouse emissions and food insecurity.
Within our problem domain we identified several key stakeholders: households, restaurants,
supermarkets, sustainability activists, charities, disadvantaged people, government and waste
collection. These are represented in the rich picture, (shown below) that we created showing how they interact with each other and the problem domain.
FOOD WASTE
Across stakeholder interviews conducted, one insight stood out: food waste is rarely caused by malice. Their behaviour was primarily motivated by cost, convenience and a lack of awareness or indifference towards food waste.
​
Key Behavioural Drivers (from interviews):
-
Cost pushes users to buy in bulk even when they can’t finish the food.“I buy the big packs because it’s cheaper… but I end up throwing a lot away.” - Household participant
-
Convenience determines whether people act sustainably.“Honestly I just don’t want to put effort into it… I don’t really care that much.” - Household 1
-
Indifference grows when waste feels inevitable or low-impact.
-
Lack of transparency makes people hesitant to share or donate food.
​
From this, we identified a paradox:
Lower unit prices encourage over-buying → more food waste → waste-management programs get more complex → less-conscious households disengage.
Our design challenge became:
"How might we give households the financial benefits of bulk-buying, without the waste that bulk-buying creates?"
Based on the problem statement and domain research, we executed our solution - ShareCart - through the following iterative process of ideation, prototyping and testing.
Solution
SHARECART
Ideation
Our early design proposals were largely shaped by stakeholder interviews conducted in the initial stages of research. Each group member focused on addressing pain points identified from their respective stakeholders, ranging from households and restaurants to sustainability activists and disadvantaged people. A recurring theme across stakeholder groups was that spending habits were mainly motivated by considerations of cost and convenience, rather than by moral or environmental concerns about food waste. This insight became a key factor in shaping our ideation process, prompting us to consider solutions that provide tangible, practical benefits while passively encouraging waste reduction rather than relying solely on ethical motivation.
EVALUATING CONCEPTS
Personas
To ensure ShareCart addressed the full complexity of real food-waste behaviours, we developed a diverse set of 5 personas that went beyond a single “typical” user. Instead of focusing only on our primary audience - small households motivated by cost - we intentionally designed personas representing edge cases, conflicting motivations, and varying levels of waste-consciousness. This allowed us to test our concept against users who might have constraints that differ from the mainstream. By grounding each persona in insights from stakeholder interviews that we conducted, we ensured that ShareCart remained usable, intuitive, and valuable across a spectrum of needs. This broad personas set ultimately helped us design a system flexible enough to appeal to different household types while still targeting food-waste reduction in meaningful, behaviour-led ways.
DEVELOPING USE CASES
Main Design Concept
ShareCart is a shared ordering system that lets households buy bulk directly from producers at lower prices while only taking the portions they need, reducing both cost and excess waste. It is especially beneficial for smaller households who face higher unit costs or unwanted surplus when buying in bulk, offering a more flexible and convenient alternative—even if it occasionally requires waiting for group orders to fill. Producers gain predictable sales without relying on supermarkets, while users can start private group orders, join existing ones, or add items to a wishlist to be matched with others. The concept directly responds to a core paradox in the domain: lower unit prices encourage overbuying and waste, while existing waste-reduction programs often add complexity that discourages less waste-conscious households. By appealing to cost and convenience rather than moral obligation, ShareCart motivates more types of users to buy only what they need, making waste reduction an accessible by-product rather than an imposed goal.
SHARECART
Final Prototype
This prototype demo showcases how ShareCart enables households to pool their grocery purchases, split bulk items seamlessly, and minimise food waste through smarter shared ordering. The walkthrough highlights key interactions that simplify the process—from joining an order to receiving transparent pickup and delivery details.