Google has announced the finalists of this year’s Google Science Fair and the line-up is impressive. But among the 15 inventions designed to make the world a better place, Cynthia Sin Nga Lam’s submission is definitely a major standout. Concerned about the millions of people living without energy and water, the 17-year-old student scientist from Australia built H2Pro – a Portable Photocatalytic Electricity Generation and Water Purification Unit that produces both clean energy and fresh water at the same time.

With the H2Pro, Cynthia aims to tackle two problems at once: how to provide clean water and electricty to the many people around the world who have neither. Currently 780 million people lack access to clean water, while 1.2 billion live without electricity. The H2Pro could change that using photocatalytic technology, which simultaneously purifies water and generates electricity using only sunlight.

In her application, Cynthia explains that while investigating photocatalysis, she stumbled upon the idea of the H2Pro.

“In photocatalysis, not only water is purified and sterilized, but hydrogen is also produced through water-splitting, which can be used to generate electricity,” says Cynthia.

Related: 11-Year-Old’s Fantastical Water-Purifying Machine Wins 2014 Doodle 4 Google Competition

“The entire process only needs titania and light — no additional power source is required. However, hydrogen production is generally low since photoexcited electrons tend to fall back to the hole (i.e. photoinduced electron-hole combination.) Fortunately, it can be overcome by adding reductants, while some organic pollutants serve such purpose. Hence, I propose to combine the two mechanisms together to enhance the yield and lower the cost of hydrogen generation, meanwhile efficient water purification can also be achieved.”

While there are other designs that have proposed a similiar method, they often require an external power source, which means they can’t be used in remote locations. Cynthia aims to change that via photocatalysis, which can be applied in a manageable scale that allows water purification and electricity production to be economically and sustainably performed. It’s an excellent humanitarian design and a strong contender for the top prize. Good luck Cynthia!

For information on all the other finalists, click here.

+ Google Science Fair