Brightly coloured motorised tricycles are a national phenomenon in the Philippines. Numbering around three-and-a-half million nationwide, the rainbow-painted vehicles serve as the country's taxis and goods transporters.

But as cheerful and effective as they are, tricycles churn out around 10 million tonnes of carbon dioxide every year, and add to the Philippines' considerable air pollution problem.

In a bid to fix this, the Asian Development Bank is funding one potential solution - tricycles that run not on petrol, but on electricity.

In the next 10 years the government wants to bring in more than five million electric tricycles across the country, three million of which will be the capital, Manila.

E-tricycles do not emit any fumes directly, and according to the Asian Development Bank their carbon footprint is less than one quarter of that of petrol-fuelled tricycles.

There are other benefits too. Although they cost more to buy initially, the running costs of e-tricycles is much lower. Over 100km, a normal tricycle needs about $6 of petrol, but an e-tricycle needs only $1 worth of electricity.

With 20 pilot e-tricycles already up and running in Mandaluyong City, Omar Khalifa takes a ride and discovers why, with the help of new charging infrastructure, e-tricycles could become the Philippines' new transport of choice.

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