With the temperature and humidity dropping in October, and Hong Kong’s climate becoming more bearable, Green Sense hopes more people will take part in its annual “No Air Con Night” this year.
The local environmental awareness group launched the initiative in September 2010, but is still not convinced it has persuaded enough Hongkongers to switch on their fans for a night instead of using air cons.
“Rather than picking a night in July or August each year, we chose September, and this year it’s October 7,” says Gabrielle Ho Ka-yee, Green Sense’s project manager. Holding the occasion a month later is more realistic if they want a greater number of people to take part, she says. An estimated 88,000 households showed support for the campaign last year.
The government’s Electrical and Mechanical Services Department estimates air conditioners consumed 13 billion KWH of electricity in 2013, accounting for 30 per cent of Hong Kong’s total energy use. Residential and commercial buildings contribute 60 per cent of Hong Kong’s greenhouse gas emissions, it says.
Ironically, we are locked in a vicious circle: as we burn more fossil fuels for electricity generation, we are polluting the atmosphere with ever more heat-trapping gases, creating a climate in which we are more likely to want to turn on air conditioners.
Many Hongkongers remain unaware of how wasteful they are, according to Ho. She says she often speaks to students at environmental awareness seminars who understand that air conditioners are power hungry, simply because they know their parents’ electricity bills rise in the summer. Although some say they know an air con needs to blast out about 2.5kWh to cool a 10 square metre room, none has any idea a double-decker bus consumes 100kWh, or that auditoriums, gyms, offices and shopping malls gobble up hundreds or thousands of kWh.
“We’re so used to air conditioning wherever we go, without realising the environmental impact,” Ho says.
“Is it necessary to turn up the air conditioner so we can wear a suit in the office or have hot pot in a restaurant while it’s blazing outside?” Ho asks, adding that she wears a light cotton blouse in the summer, and always uses a fan rather than air conditioning at home and in the workplace. “When we go out during the day, do we leave the air conditioner running so we can return to a cool house?”
Ho also points out that buildings and buses are fitted with sealed windows that cannot be opened to enjoy a cooling breeze. They also leave us vulnerable to the spread of allergies and viruses from dirty filters.
“Our body’s natural adaptation to heat is diminished from overuse of air conditioning,” Ho says. “When we take kids out on field trips, they refuse to get out of the bus.”
However, there are indications that Hong Kong is beginning to make some headway in energy conservation.
“Although Hong Kong’s energy consumption is going up due to a rise in the population, our energy efficiency based on economic production is also improving,” says Barry Chu Kei-ming, a chief engineer at the government department.
In 2012, in an effort to encourage energy conservation in common indoor spaces – which are often so cold, people wear jackets and scarves – the Environment Bureau and the department launched the Energy Saving Charter. About 175 shopping malls, and 2,000 offices and housing estates, have since signed up. Although the charter is not legally binding, it urges participating properties to regulate temperatures to no lower than 24 degrees Celsius – resulting in a 20 per cent reduction in electricity consumption.
Up to June 2016, of 40 participating malls the department spot-checked, only one was found to be cooler than 24 degrees and was notified.
The Buildings Energy Efficiency Ordinance came into effect in 2012. The law requires that all commercial spaces larger than 500 square metres be audited every 10 years for energy efficiency in terms of lighting, air conditioning, electrical supply, lifts and escalators. The department reports a compliance rate of 85 per cent among buildings whose owners have submitted an early audit.
New technology is playing a big role in cutting consumption in public places and homes. Smarter air-con units have come on the market in recent years, although many have not been warmly received by consumers because they are costly. Among “grade one” air-conditioners – certified by the department as the most energy efficient – the more expensive “inverter” home unit boasts energy savings of 40 per cent. It uses an inverter to modulate the power and refrigerant supply by stabilising the temperature – thereby saving energy – unlike the traditional stop-start compressor.
Another development is the heat pump – an all-in-one air-conditioner/heater and water heater, which operates on the principle of heat recovery.
“An air conditioner provides cooling for inside, but we are throwing out an equal amount of heat, and in turn paying the gas or electric company to heat our water,” says John Williams of Hotspot Energy, a US HVAC (heating, ventilation, air conditioning) company founded by solar energy specialists.
It describes heat recovery as the “world’s most promising untapped energy source, which causes no pollution, oil spill or radioactivity [and] doesn’t depend on wind or sunlight”.
For one unit of electricity used by the heat pump, it produces more than one unit of heat and cold energy. When in operation, expelled heat from the air conditioner is channelled to heat the household water supply.
“In US industries, the HVAC and refrigeration energy load often account for more than 50 per cent of a building’s energy consumption. So these areas of great concern also present an area of great opportunity for energy-saving innovations,” says Jay Fechtel, president of Olive Tree Energy, which manufactures HVAC energy-saving goods.
The heat pump system has been widely applied in premises in the US ranging from restaurants and hair salons to hotels and gyms, Fechtel says.
In Hong Kong, the heat pump is being used in some commercial premises, such as swimming pools, and is just beginning to be introduced to households.
Joe Wong Kai-tat, a civil engineer with a family of eight living in a Sai Kung village house, says he has seen substantial savings on water heating since installing a heat pump.
“We used to spend HK$20,000 a year on water heating. We used LPG tanks, which were a pain, especially when the hot water ran out in the middle of a shower,” Wong says.
A few years ago, he bought a heat pump in China and it has slashed his water heating bill by half. The pump quickly paid for itself, he says. He quit his job and set up his own company, JWSavvy Tech Engineering, which sells heat pumps made by China-based New Energy Technology Development.
Wong says that although there are about 400 heat pump manufacturers in China, Hongkongers are only just becoming aware of the technology, and are put off by the pumps’ high cost. A compact water-heating unit that integrates the pump and tank extracts thermal energy from the environment to heat water. It fits easily into a small home and costs HK$12,000 to HK$15,000, Wong says.
Scientists are increasingly looking beyond our dependency on fossil fuels, and beyond renewable energy technologies such as solar and wind power. One person at the forefront of this is US health education specialist Valerie Robitaille, who is building a generator that extracts free energy from the unlimited quantum field of subatomic particles. Such a generator is envisioned to eventually power our homes off the grid.
Although it might sound futuristic, it’s not a new idea. Robitaille, who says the generator was inspired by free energy pioneers Ronald Brandt, John Ecklin and Nikola Tesla – Elon Musk named his electric car company after the latter – who were attempting to build the model a century ago.
“We open-sourced the plans for the generator for co-development around the world,” says Robitaille, whose husband, James Robitaille, a retired electrical engineer, started the project. Several countries have downloaded the plans and built prototypes of the generator. James has also visited China to seek manufacturers for moulds and other parts of the generator.
She believes people everywhere should join together to develop, produce and install free and clean energy sources. “It’s about putting the power of the planet, and the money to be made in it, back into the hands of the masses rather than the few,” she says.