To reduce atmospheric concentration of carbon dioxide, green energy is used as an alternative energy source. Generating energy with green energy source should not limited to large-scale power plant, but also a small part in a portable device. In Hong Kong or other urban cities, many people spend most of their time indoor than outdoor. Hence, it would be attractive to make a chemical product that can be charged indoor, and used indoor or even outdoor. The best choice for this should be photovoltaics. This thesis aims to introduce a general product design approach to integrate photovoltaics to a device with specialized in indoor use.

First, we begin with market study. We collect consumers’ preferences and convert them into product attributes. For example, the weight, volume and shape sho...[ Read more ]

To reduce atmospheric concentration of carbon dioxide, green energy is used as an alternative energy source. Generating energy with green energy source should not limited to large-scale power plant, but also a small part in a portable device. In Hong Kong or other urban cities, many people spend most of their time indoor than outdoor. Hence, it would be attractive to make a chemical product that can be charged indoor, and used indoor or even outdoor. The best choice for this should be photovoltaics. This thesis aims to introduce a general product design approach to integrate photovoltaics to a device with specialized in indoor use.

First, we begin with market study. We collect consumers’ preferences and convert them into product attributes. For example, the weight, volume and shape should be limited so the product is portable or mobile. At the same time, we have to ensure the product can be run without external charging. In other words, energy generated from the photovoltaic module and energy stored in the battery should be able to cover the energy consumption. The appearance of the product may become a charm point. Besides, we may have to study competing products so as to beat them and enter the market.

Then, we move to product design part. From the product attributes, we convert them into quantifiable product specification, which includes the key ingredients and the structure of the product. We have to use heuristics to select photovoltaic and battery materials, and integrate them into a single device as the final product. The voltage of the photovoltaic module, battery, and device should match each other. Also, the photovoltaic module and battery should not change the size and weight of a product significantly. Under designated conditions, the photovoltaic module should be able to charge the battery to provide daily energy consumption of the product within reasonable time. For example, our headphone should be able to function an hour with three hour charging in office.

In this thesis, we will demonstrate with two examples: wireless headphone and alarm clock.