How I used AI Video Generation for My Hackathon Submission
Aug 22, 2025
I used AI video generation tools Veo 3 Flow and Replicate to create a 3-minute hackathon demo video for NHS Buddy. Here’s what worked and what didn’t.
This blog post details my experience using AI video generation tools to create a compelling 3-minute video for my Kaggle - The Gemma 3n Challenge submission, focusing on a product called NHS Buddy. The product is an on-device medical assistant designed to support doctors and hospital staff with administrative tasks, critical alerts, and medical information, with the goal of "helping those who help us."
Given the three-minute limit, it had to concisely explain the context of the product while also demonstrating its core features. Here's the final video that we submitted.
The Video Storyboard: My Blueprint for Success
Before generating any video clips, I created a detailed storyboard. I broke each visual element into a “byte” or a single prompt. For example: a doctor checking a patient chart, receiving a critical alert, or reviewing medical data on a device.
This approach ensured that I had a clear vision for the final video and a systematic way to create the necessary clips that fit together seamlessly.
Veo 3 Flow: The Initial Go-To
My first choice for video generation was Veo 3 Flow. My experience with it was generally positive, and it helped me create a lot of the initial content for the video.
The Pros:
Prompt-to-Clip Efficiency: For the most part, I found that I could get the desired results within just a few attempts. I just needed to write the prompt, and Veo3 Flow would quickly generate a clip that matched my vision.
Batch Generation: A big plus was that it generated two videos at a time. This sped up the process, giving me more options to choose from and allowing me to progress through my storyboard more quickly.
High-Quality Output: The quality of the generated videos was impressive, which was crucial for a professional-looking submission.
The Cons:
Resource Intensive: The main drawback I encountered was the expense. AI video generation can be a costly process, and this was a significant factor in my decision to look for an alternative.
Inconsistent Outputs: While the model often retained elements I liked, it was a bit unpredictable. For example, if I wanted to introduce a new element in a subsequent generation, I would often find that the video had added the new element but removed something it was getting right all along. It felt like I was constantly trying to get the "perfect" video that had all the right elements.
Despite this, it was better at retaining elements than Replicate, which is why I often got the desired results within just a few attempts.
Replicate: The Backup Plan
When I started running out of credits on Veo3 Flow, I turned to Replicate. It was a more programmatic solution that offered access to the same Veo3 models, as well as others like the Wan model.
The Pros:
Cost-Effective: Replicate was a much more affordable option, which was a huge benefit, especially for a personal hackathon project.
Model Variety: It gave me access to a range of multiple models, which could be useful for a variety of projects and opened up creative options.
The Cons:
Programmatic and Less User-Friendly: The ease of use was a definite step down from the more streamlined interface of Veo 3 Flow. Since it was programmatic, it required more technical know-how and was a bit more cumbersome.
Inconsistent Generations (Again): The same issue I had with Veo 3 Flow persisted here, but it was more pronounced. I would often get two videos that each had a different element I needed, but neither had all of them combined. This meant a lot more trial and error to get the right clips
Slower Generation Time: It also seemed to be a slower process, likely because it only generated one video at a time, which reduced my overall output compared to Veo 3 Flow.
Key Takeaways
Both Veo 3 Flow and Replicate were instrumental in bringing my storyboard to life and producing a professional, engaging demo video for NHS Buddy. The main lessons I learned:
A storyboard is essential.
Having a clear plan made the generation process much smoother.
Expect iteration.
AI video tools are powerful but unpredictable. Getting the right clip often required trial and error.
Balance quality and cost.
Veo 3 Flow delivered higher efficiency, while Replicate was more budget-friendly. Using both strategically worked best.
Ultimately, these tools allowed me to build a clear, compelling narrative within the hackathon’s three-minute video limit.
As AI video generation continues to evolve, I see it becoming a standard tool for hackathons, prototypes, and product storytelling.