Difficulties Of Working With Solar In Hong Kong
Being an interior designer in Hong Kong I’m often found gazing out of clients rooftops looking for way to beautify them. In this one case I was out looking for a space to install a solar panel and to my surprise while looking among the skyscrapers I noticed one solar panel on a residential rooftop and thought Halleluiah finally one panel. Did you know in 2012, Hong Kong relied on coal (53%), nuclear (23%), natural gas (22%) and a very small amount (2%) of renewable energy for its electricity generation. As coal-fuelled production units start to retire in 2017, the Government plans to raise the share of natural gas to 50% in 2020 while maintaining the share of nuclear power at present levels. Many world cities have ambitious aims to reduce their GHG emissions by 80% by 2050 or sooner as part of the Carbon Neutral Cities Alliance. Essentially, this would mean that these cities will have to convert their energy generation to mainly renewables.
Hong Kong is not part of this Alliance and is far from supporting renewable energy. In cities such as New York City there are options on your electricity bill to select a percentage of your usage from wind power as well as options for producing your own electricity by renewables and sell back to the grid. Hong Kong is still lagging behind to implement these types of agreements with the power companies. This particular residence is located in an old walk up building in Central that provides has very little energy provision to begin with. Our client was open to using the most efficient way to generate electricity for his 400 sq ft flat and 400 sq ft rooftop. It turned out that solar panels would take up too much space to provide the energy we needed and small wind turbines were also not efficient. The best options available were to use a combination of heat pump and solar water heater. To my surprise the breakdown of cost savings is that the heat pump can save 80% of the total water heating bill and the solar water heater will save only 7%. There were a few difficulties we came across as the team tried to install the panels:
1. The space we wanted to use for installation was covered in layers of antennas and electrical wires connected to many buildings at every angle. There was no way for us to find out if the antennas and wires were even being used anymore.
2. In Hong Kong the most ideal situation is to angle the solar panel at 22 degrees south facing. However due to the density of buildings all over we needed to do a study to find out how to avoid shade from the surrounding buildings.
3. With the solar water heating panel comes a larger water storage tank/ heat pump which had to be placed in an outdoor cabinet shielded from the rain and properly ventilated.
We also set up an electricity and solar meter Efergy Panel (https://engage.efergy.com/#solar ) which calculates and provides a live feed of cost per hour with immediate changes when the lights, A/C…etc are turned on. It also calculates the energy being produced by solar separately from the main power. Real time information can be seen on our client’s computer and mobile device. Heat pumps and Solar water heaters are only the start of our efforts to make our interiors energy efficient and we are continuously looking for the best collaborators in the industry to help improve our system.