His structure, which he dubs the "Smart Bus Stop", has a roof made of a light and durable material and can reflect heat well.
Fitted on a ball-joint system, the roof can be rotated and tilted to left or right, and to the front or back, when needed.
He says: "Depending on the sun's position during the day, the roof tilts to shade commuters. When the weather turns breezy, cloudy or cool, the roof pole can automatically extend itself to allow larger open-air pocket space and cool the waiting passengers."
When it rains, the roof returns to its default position - a straight, T-shaped shelter.
Mr Yuen also proposes syncing the system with real-time data from Singapore's meteorological service so that the roofs adjust automatically based on the bus stop's location.
The 39-year-old used to take a bus daily for five years from his home in Bedok Reservoir to his studio in Playfair Road. Earlier this year, he moved to live closer to his studio and now walks to work.
Recalling his experience waiting at bus stops, he says they were sweaty affairs. "Especially at noon, the sun can shine directly into some bus stops. I got relief only when I boarded the air-conditioned bus."
He also noticed people's reactions at bus stops. "Living in the tropical region, the hot weather is always an issue.
"People are visibly uncomfortable waiting at the bus stop, especially when they are exposed to the sun due to factors such as the bus stop facing the sun or a crowded space."
For his design, he says he kept to a basic-looking model and did not add any frills. It will help the Land Transport Authority save money, he says.
"Keeping the bus stop simple can lower the cost of maintenance in the long run. Design should focus on solving immediate comfort issues for the passengers, before diverting resources towards peripheral add- ons."
While some may think that the Smart Bus Stop seems like an overly- simplified solution to Singapore's perennial heat wave, Mr Yuen says: "If we can invest in design to alleviate this issue, the experience would be much more pleasant and enjoyable, especially for senior citizens.
"Who knows, it might encourage more people to take the bus."
A cool garden for shade
What: The Garden Stop
By: forest & whale
Wait for the bus under a structure landscaped with a lush green canopy and peek into the roof garden through periscopes.
Buttressing Singapore's push to become a "city in a garden", design studio forest & whale suggests The Garden Stop: a new-age bus stop that melds the structure's architecture and the environment.
In its version, commuters stepping off the bus will see a lush green roof filled with little trees and shrubs - a showcase of Singapore's variety of tropical plant species.
Argentinian Gustavo Maggio, 36, one half of the duo that founded the one-year-old design studio, describes the bus stops here as dreary, grey stops with "concrete floors and glossy, stainless-steel furniture".
"They do little to remind us of the garden city that we live in," he says. "It's a pity since bus stops - in today's rapid commute through train networks - represent a slower pace of lifeand are an opportunity for us to take time to appreciate our surroundings."
Mr Maggio and his Singaporean co-founder Wendy Chua, 32, also want to give commuters the chance to get up close with the rooftop garden, even as they wait under it.
Think exploratory periscopes that extend up into the roof for people to peek at the plants as well as the insects and birds that visit the garden there.
As Mr Maggio puts it: "This activates the space and creates social interaction. Peering into the garden that is above our heads, we can immerse ourselves in the present as we wait for our ride."
Mr Maggio and Ms Chua are better known as being part of Outofstock, an award-winning design collective which has two other members.
Forest & whale's recent work includes the sleek interiors of bakery- cafe Plain Vanilla in Cluny Court that also drew inspiration from nature.
But The Garden Stop is more than just "sensorial beauty".
Mr Maggio says: "The planted roof plays a vital role in thermal insulation. Watering the plants also draws heat away through evaporation, and cools the space below."
As for shade, the roof can be designed to overhang.
Get details via an app
What: Beacon technology at bus stops
By: Plus Collaboratives
Almost everyone has a smartphone these days and many are glued to the device on their daily bus trip.
Design-thinking and research studio Plus Collaboratives rides on this detail with its take on the next-generation of bus stops, which weaves beacon technology into a commuter's journey.
Bus stops in the future should have beacons, says design director Cheryl Sim, 28. Beacons emit signals containing data, via Bluetooth and Wi-Fi, to nearby smartphones and tablets. An app on the commuter's device picks up the signals and sends an alert, giving users "personalised" real-time information such as the weather conditions at their stop.
Ms Sim, who came up with the idea with creative director Mervin Tan, 34, and design research director Low Jue Ming, 28, says: "It was an obvious idea as most people use a smartphone today. Why not use it to transmit information about your journey?"
It could also do more. For example, if two arriving buses take a commuter to the same destination, the app can show which takes a longer route. Or it can connect commuters with friends who are nearby and update them on their travel times if they are meeting at a bus stop.
Mr Tan, who takes public transport about thrice a week, draws on his experience taking buses in Australia, where he attended university. There, he says, bus schedules were very accurate, so commuters could plan their schedule to a T.
It is different here, he says. But instead of pressing bus drivers to arrive at stops at a scheduled time - since traffic conditions vary - beacons can send information to commuters along the way. He says: "Current travel apps mostly offer general information. We want ours to run in the background as you travel and act like a personal assistant that connects you better to places and people."
The team says the look of bus stops does not need to change as the "Land Transport Authority has made bus stops well".
But Mr Tan asks: "What about the 'software' in commuting? Efficient mobility has to be about more than just physical commuting."
Solar panels to harness energy
What: A bus stop for everyone
By: Ong Shi Ke
This bus stop has something for everyone.
Cyclists and those on scooters can secure their two-wheelers at a kiosk adjoining the structure before hopping onto a bus. Commuters can quench their thirst at water coolers, while those with low battery life on their mobile devices can power up.
There is also an audio aid that tells those who are visually disabled when their bus is arriving.
The design is also kitted out with features to help waiting commuters deal with the hot tropical weather. The rectangular roof with rounded edges, for example, is designed to keep the space naturally ventilated, keeping commuters cool on hot days, says its designer, engineering graduate Ong Shi Ke.
The roof also has solar panels, from which energy is harnessed to power the charging points, making the structure eco-friendly.
Ms Ong says: "Some bus stops are exposed to much sunlight. Why not use that energy to run the other features of the bus stop?"
On stormy days, vertical acrylic panels fitted to the sides of the bus stop can be positioned at an angle, so that rain does not splash on waiting commuters. The panels are clear, so commuters are still able to see which buses are arriving.
The graduate from the Singapore University of Technology and Design says she drew on her own commuting experiences when designing her bus stop, which she has not named.
The 22-year-old, who rides the MRT daily and takes the bus once or twice a week, says that train stations have charging points, free Wi-Fi and are well-ventilated or air-conditioned so she is kept cool.
Some bus stops also do not have electronic boards that show when buses are arriving, so it can be a guessing game as to how long she has to wait. She notes: "Waiting for a bus is not as pleasant as waiting for a train."