Hi Reddit! We are Richard Hopkins and Andrea Holden, Team Principal and Team Manager of Sunswift 7 - a solar-electric car designed and built by university students here at UNSW.

Last year our team took Sunswift 7 to the Australian Automotive Research Centre in Victoria to attempt to set the Guinness World Record for the Fastest EV over 1000km on a single charge.

We completed the 1000km in 11 hours and 52 minutes - and at the start of the year, the Guinness team confirmed that we got the record.

This year, we’re gearing up to compete in the Bridgestone World Solar Challenge and will be starting work on the next iteration of the car, Sunswift 8.

We previously shared some photos of Sunswift 7 to r/ pics and loved answering your questions so we thought we’d jump back on to chat about the project, solar-electric cars and all things engineering!

Ask us anything!

Proof pic from the workshop!

Alrighty - that's all we have time for today folks! Thanks for the great questions!

We'll keep an eye on the post throughout the day and jump back in where we can!

If you're keen to learn more about Sunswift Racing and what we're working on you can check our website: https://www.sunswift.com/

Cheers, Richard and Andrea.

Comments: 32 • Responses: 9  • Date: 

Tiny_Discussion89458 karma

This is such a cool project! How likely is it solar cars ever come to market?

unsw9 karma

Good morning, I really can’t see any reason why PV / solar won’t have a part to play in automotive in the future. We are a long way off it having the ability of being the only energy solution.

-Richard

webrodie5 karma

How do you manage to go so far on a single charge? Do you have a special battery? Why can't they be used on normal road cars because way more people would buy an EV that could go 1000km without having to be re-charged.

unsw13 karma

The key to our success with Sunswift 7 is actually the efficiency on all aspects of our car. Our motors are 99% efficient which is significantly more than standard electric motors, the aerodynamic drag on our car is half that compared to a Tesla and the car only weights 580kg. All of these things mean that it is effectively “sipping” energy as it drives.

Not to mention the impact of solar as well, obviously being a solar car – we estimate that for the world record, the solar increased our range of approximately 30% which is a huge help.

And to top that off, our battery is only 38kWhs. So we’re able to achieve a range of double a Tesla with close to half the battery size which we’re pretty proud of. A Tesla model S has an energy consumption of 20kWhs/100km, Sunswift 7 has is 3.8kWh/100km.

-Andrea

jordainty4 karma

What’s the process of building the car like? Is it from scratch or do you retrofit an existing car body with solar parts?

unsw8 karma

For Sunswift 7, we designed it from a completely blank sheet of paper. The chassis for example was manufactured bespoke by us with one of our partners up in Gosford, McConaghy, over a 3-month period. While we did have a few existing parts that were suitable on the shelves before we started developing Sunswift 7, a large proportion of our technology was designed and manufactured by us.

In terms of the process, we have 4 phases within our team; design, manufacture, assembly and testing. While Sunswift 7 is a “complete” car, we’re constantly innovating and developing our technologies.

-Andrea

CunningFudge3 karma

How many students are involved and how do you choose who can be part of the team?

unsw9 karma

We have around 100 undergrad students at any one time. We recruit throughout the year as its natural for students to graduate.

Those 100 students sit across 8 academic disciplines: Mechanical, Electrical, Renewables, Computer Science, Chemical, Systems, Industrial Design and Material Science. 30% are female which is fantastic and our retention rate is around 90% so a 2nd year will normally be part of the team until they graduate as a 4th year.

We recruit three times a year and it's open to anyone here at the university!

Also, Sunswift Racing is a course, so students earn units of credit towards their degree.

-Richard

Natrecks3 karma

How cool! What will be new in the Sunswift 8 compared to 7?

unsw4 karma

Sunswift 8 will be a departure for the team in regards to traditionally building cars for the Bridgestone World Solar Challenge.

There are so many technologies that because of regulation we are unable to explore.... hydrogen being a very good example.

We're keen to see what we can do without regulations.

-Richard

extra_specticles1 karma

Hi there. Congratulations. That's amazing work!

What are the students who took part, likely to do once they move on from the project?

unsw2 karma

A lot of our students that finish up or graduate from university often don’t want to leave!

We have had students stay on doing PhD’s and Master’s just so that they can stay involved in the project. For me personally, I joined this project as a student in April of 2020 and graduated only a few weeks ago and have now been employed to help Richard run the project which is great to be a part of.

As for what’s going to happen in the future, I’m not 100% sure at the moment!

A lot of the skills that our team learn while working on such a dynamic project like Sunswift Racing are directly transferrable to many industries for their future careers. Additionally, lots of students go on to do further work with our industry partners. We also have around 30+ alumni that have gone on to work for Tesla and SpaceX.

-Andrea

PeanutSalsa1 karma

What obstacles do solar cars face in being adapted into the everyday market?

unsw3 karma

Good question. The obvious one is having or not the sun shining in the sky.

However, solar does perform on bright cloudy days. As mentioned in a previous question I don’t see solar as ever being 100% of the solution. It can quite easily have a part to play within the whole energy system of the car.

-Richard

ssouthurst1 karma

So you broke this record in Victoria - imagine what you could do if there was some sun! (Ballarat resident).

What has the progression in performance/efficiency been like across the various Sunswift models?

unsw2 karma

Good Morning, we actually had a day of reasonable weather for the attempt. Quite barmy for Victoria. :)

It’s not straightforward to compare progress across the models. Sunswift I, II, III & IV (IVy) all competed in the Challenger class which are the cars fondly named ‘Cockroaches’, basically a big solar array on wheels.

Sunswift V (eVe), VI (Violet) & 7 compete in the Cruiser class with doors and 2 or more seats. Regardless Power Optimisation, Weight, Low Rolling Resistance, and good Aerodynamics are the key pillars. Research and advancements in all of these areas move the project up the innovation curve.

-Richard

RocketBoy45791 karma

[deleted]

unsw1 karma

Good Morning UNSW student, I thought you were going to say that you were asking for a friend!

Sunswift Racing is a VIP, Vertically Integrated Project. A VIP is technically a course where you get a mark and units of credit... However, the course is spread over 3 terms rather than 1 and it's at the end of your 3rd term where you receive your mark and 6 UoC.

All 3 terms have to be done consecutively. It’s 150 hours but across 3 terms (30 weeks) so 5 hours per week although I don’t know one student who only does 5 hours per week! The dynamics of the project and how you can learn more than you would ever imagine mean students do much more.

You can technically join as a 2nd year and stay until you graduate. Only very few only stay for one year.

Feel free to email me or visit the ChallENG website for more info.

-Richard