Earth Hour – The Asymmetry Principle vs The Rebound Effect
Earth Hour Singapore is back again and takes place this Saturday, 27 March 2010. Individuals, organisations and businesses are encouraged to switch off their lights for one hour from 8.30pm to 9.30pm, or longer. Earth Hour is organised by WWF and is “a call to stand up, to take responsibility, to get involved and lead the way towards a sustainable future.”
The switching off of lights is a symbolic act for everyone to take responsibility and fight climate change. Find out more about what you can do and pledge your support for Earth Hour.
Earth Hour has been successful in gaining support and participation over the past few years. For this year’s Earth Hour, we would like to remind everyone that Earth Hour is not just about switching off lights, it’s about two key forces at work – The Asymmetry Principle vs The Rebound Effect:
The Asymmetry Principle
In his book, The End of Energy Obesity: Breaking Today’s Energy Addiction for a Prosperous and Secure Tomorrow, energy economist Peter Tertzakian describes The Asymmetry Principle as:
the lopsided relationship between how much raw energy is available at the primary source — for example, at a natural gas well — and the small fraction of energy that is actually put to useful work at the consuming end — for example, in lighting a light bulb. The principle states that a unit of energy saved at the consumer level amplifies into multiple units of energy saved at the source. In effect, the asymmetry principle exposes the high levels of inefficiency in society’s energy systems and highlights the tremendous leverage offered by efficiency gains and conservation in mitigating source energy consumption.
He gave the example of a light bulb:
- 100 energy units of natural gas at source
- 40 energy units remaining due to conversion to electricity
- 35 energy units remaining due to transmission losses
- 2 energy units remaining due to conversion to light
In this example of a light bulb, reducing the consumption of one unit of energy (as light) actually saves the production of 50 units of energy (as natural gas) if you account for the inefficiencies and energy losses in fuel production, electricity generation, electricity transmission and thermal conversion to light.
To put it simply, when you switch off the lights and save X units of energy, you are actually saving more than X units of energy as the energy savings amplify back to the energy source.
Therefore, energy conservation or reducing your energy consumption plays an important role in reducing carbon emissions. When you switch off your lights or appliances at home during Earth Hour, it is not merely the act of pressing a switch but the multiplying and amplifying effects of conserving the energy resources upstream.
However, energy conservation must be done by everyone daily to make a significant difference such that The Asymmetry Principle plays out. Take the example of last year’s Earth Hour:
In Singapore, turning off lights and electrical appliances during Earth Hour saw a 42-megawatt drop in electricity demand. This is equivalent to 40 per cent of the electricity demand in Ang Mo Kio for that hour, said Energy Market Authority (EMA).
However, there was no real decrease in carbon emissions.
Since we only used 1 per cent less electricity as we normally would have in that hour, the generation companies (gencos) burnt just as much fuel as usual, said EMA.
For actual reduction in the fuel usage and carbon emissions, everyone in Singapore (households and organisations) must play a part in energy conservation on a daily basis to reduce Singapore’s energy demand. Ad hoc or yearly Earth Hour actions will not be sufficient to effect an actual change in the reduction of energy resources and carbon emissions.
The Rebound Effect
The Rebound Effect usually refers to the behavioral responses to the introduction of new energy efficiency technologies or measures, which tend to offset the actual benefits of the new technology or measures. In other words, actual energy savings is less than expected savings.
For example, if you replace a 20W incandescent light bulb with a 10W energy efficient compact fluorescent bulb, the energy saving should be 50%. However, the actual energy saving is usually less than 50% because as you find that you pay less for lighting, you tend to be less concerned with switching it off. The increased usage thus eat away some of the energy savings from the more efficient light bulb.
Here, we will adapt The Rebound Effect to explain that the actual energy or carbon emission savings could be less than the expected savings from energy conservation. When you reduce energy or carbon emissions from one activity but use more energy or generate more emissions by switching to other substitute activities, then the actual savings is less than expected savings.
For example, you usually read a book on a Saturday night. But to support Earth Hour, you switch off your lights, thus saving X units of energy. In the dark, you can’t read so you switch on the TV and watch it for the whole night. The actual energy savings is thus less than the expected X units of energy savings.
Or instead of staying at home, you decide to drive your car to an event that celebrates Earth Hour. The additional carbon emissions could be more than the expected emission savings from switching off the lights.
You should still support Earth Hour but remember The Rebound Effect and remind yourself that the Earth Hour activities you take part in should not be causing more energy consumption or carbon emissions as compared to your usual activities.
The Asymmetry Principle vs The Rebound Effect
Earth Hour is really about The Asymmetry Principle vs The Rebound Effect. We need to see more of The Asymmetry Principle and less of The Rebound Effect.
We need more people to switch off their lights and reduce their energy consumption daily so as to amplify the energy savings at the source. We need less people to switch to other substitute activities that consume more energy or generate more emissions.
So remember for this year’s Earth Hour, everyone must take action to conserve energy daily and ensure that our actions do not contribute to the problem we are trying to solve.
Overview of the Energy Situation in Singapore
May 14, 2009 by Eugene
Filed under Issues and Policies
This is an overview of the energy situation in Singapore in terms of Electricity Consumption; Energy Consumption; Energy Intensity; Discrepancy Between Energy Statistics; and Energy Efficiency Policies.
1. Electricity Consumption
According to the National Energy Policy Report, the power generation sector accounts for 51% of the fuel consumption in Singapore and the fuel is used to generate electricity for the following sectors (in 2005):

There are currently eight electricity generation licensees operating in Singapore, regulated by the Energy Market Authority:
- Senoko Power Ltd (3300 MW)
- PowerSeraya Ltd (3100 MW)
- Tuas Power Ltd (2670 MW)
- Keppel Merlimau Cogen Pte Ltd (1400 MW)
- Sembcorp Cogen Pte Ltd (785 MW)
- National Environment Agency (251 MW; electricity from incineration plants)
- Island Power Company Pte Ltd (not in operation yet)
- Keppel Seghers Tuas Waste-to-Energy Plant Pte Ltd (not in operation yet)
Singapore’s total electricity consumption and electricity consumption per capita from 1990 to 2007 is shown in the graph below, based on statistics from the Energy Market Authority and the Singapore Department of Statistics.

Singapore’s electricity consumption is increasing steadily each year, and has increased by 2.6 times over the past 17 years. Electricity consumption per capita increased at a slower rate by 1.8 times over the past 17 years and remained relatively constant from 2005 to 2007, perhaps an indication that the government’s energy conservation efforts are paying off.
.
2. Energy Consumption
There is some dispute on whether Singapore is energy intensive and a big consumer of energy per person in the world, which arises due to the different sources of energy statistics used. There are two commonly quoted sources of energy statistics – the Energy Information Administration (EIA) and the International Energy Agency (IEA).
The graph below shows the energy consumption per capita for selected countries in 2006 based on statistics from EIA’s International Energy Statistics and IEA’s Key World Energy Statistics 2008. If the EIA data is used, the energy consumption per capita for Singapore is higher than the US, other developed countries and the world average. If the IEA data is used, the energy consumption per capita for Singapore is lower than other developed countries such as the US and Finland.

.
3. Energy Intensity
Energy intensity is usually used as an indication of the level of energy efficiency in a country and is measured in terms of energy consumption per dollar of gross domestic product (GDP). A low energy intensity means that the country is able to produce each unit of output using less energy.
The graph below shows the energy intensity for selected countries in 2006 based on statistics from EIA’s International Energy Statistics and IEA’s Key World Energy Statistics 2008. If the EIA data is used, the energy intensity for Singapore is higher than the US, other developed countries and the world average. If the IEA data is used, the energy intensity for Singapore is comparable to other developed countries such as Finland and the US.

.
4. Discrepancy Between Energy Statistics
The discrepancy between EIA and IEA statistics is due to the different calculation of energy consumption. According to EIA’s International Energy Statistics, the energy consumption for Singapore is 53.98 Mtoe. On the other hand, the IEA’s Key World Energy Statistics 2008 shows that the energy consumption for Singapore is lower at 30.67 Mtoe.
The energy consumption based on the EIA is about 43% more than that of the IEA. This is because EIA includes marine bunkers (deliveries of oils to ships for consumption during international voyages) in its calculation of energy consumption and as Singapore is the largest marine bunkering centre in the world, our energy consumption is thus overestimated, which in turn leads to higher energy consumption per capita and energy intensity for Singapore. On the other hand, IEA excludes marine bunkers from its calculation of energy consumption.
The Ministry of Trade and Industry and the National Environment Agency has cited the IEA’s statistics as it gives a more realistic representation of Singapore’s energy consumption. A paper titled Benchmarking Singapore’s Energy Intensity (published in the Economic Survey of Singapore, Third Quarter 2006) says that:
Among the three sources of data, IEA’s numbers paint a more accurate picture of Singapore’s true energy intensity, as IEA has stripped away marine bunkers from its calculation of energy consumption. Singapore is the largest marine bunkering centre in the world. In 2003, we supplied about 20.8 million tons of bunker oil to ships. EIA’s and BP’s data overestimated Singapore’s energy intensity because they attributed marine bunkers as energy consumed in Singapore.
And concludes that:
After accounting for marine bunkers, Singapore’s energy intensity is roughly on par with countries of the same level of development. Compared to less energy intensive economies, Singapore’s higher energy intensity is due mostly to the use of energy in the manufacturing sector, the consumption of fuels as feedstock in the petrochemicals industry and the sale of jet fuel to the international civil aviation sector.
.
5. Energy Efficiency Policies
Regardless of the dispute on Singapore’s energy intensity, the government is committed to taking steps to reduce our energy consumption. According to the Energy Efficient Singapore website, Singapore’s energy intensity dropped by 15% from 1990 to 2005 (see graph below) and has been decreasing steadily since 2002, likely due to the use of better and more efficient technology in the power generation and other sectors.

Singapore’s key strategy to reduce greenhouse gas emissions is to be more energy efficient. The Sustainable Development Blueprint sets a target to reduce our energy intensity (per dollar GDP) by 20% from 2005 levels by 2020, and by 35% from 2005 levels by 2030.
To help Singapore meet the targets, the Energy Efficiency Programme Office (E2PO) is promoting energy efficiency in the various sectors through the Energy Efficient Singapore (E2 Singapore) policies and measures:

Image credit: Energy Consumption by Sectors in 2005 via National Energy Policy Report; Energy Intensity Indexed to 1990 Level via E2 Singapore; Summary of Policies and Measures in E2 Singapore via National Climate Change Strategy.
Conduct an Energy Survey to Identify Energy Saving Opportunities
May 8, 2009 by Eugene
Filed under Businesses and Organisations, Featured
An energy survey is a simple assessment of the energy use in your organisation and the aim is to identify and correct bad energy habits and practices. Start by forming a small team to conduct the energy survey, appointing an energy manager as the team leader and recruiting staff from different departments as team members.
The team will conduct the energy survey by taking a walk around the offices, building and facilities to observe what is happening on the ground, identify bad and wasteful energy use and habits, and identify opportunities for energy saving.
The survey should be conducted at different timings so as to find out the different energy usage throughout the day and at different periods. Surveys can be carried out:
- At a normal weekday during office hours
- At busy and peak hours
- At lunchtime
- After office hours
- During weekends
Use past and current utility bills, meter data, maintenance records and other energy information to help keep track of the energy usage in your organisation.
Here are some areas to take note of during the energy survey:
Office Equipment
- Are office equipment left on standby after office hours and during weekends? Can we switch them off easily?
- Does the computers, printers, photocopiers and other equipment have built-in energy saving features? Are we using these features and do we know how to use them?
- Can we use software to switch equipment off after office hours?
- Are vending machines and water coolers left on at night? Can we use timers to switch them off after office hours?
Lighting
Are lights switched off in unoccupied areas or if there is sufficient daylight? Can we reduce unnecessary lighting?- Can we use motion sensors for the stairs and carpark?
- Are lights switched off when no one is in the room or office? Who is responsible to switch off the lights after office hours?
- Are external and facade lighting switched off during the day? Can we adjust the timers to switch off the lighting earlier?
- Are light fittings arranged strategically and light switches labelled properly?
- Are we still using inefficient lighting? Can we change to energy efficient light bulbs and tubes?
Air-Conditioning and Ventilation
- Is the office too warm or cold? Can we adjust the air-conditioning temperature up to about 25 degree Celsius or at a comfortable high temperature?
- When is the air conditioning switched off and on during the day?
- Are the windows and doors open when the air-conditioning is on?
- Are the air-conditioning and ventilation system maintained and serviced regularly? Are the settings optimised and correct?
- Are there obstructions at air inlets and outlets?
Industrial Equipment
- Do boilers, pumps, fans and other equipment have the correct and optimised settings?
- Are the equipment serviced and maintained regularly?
- Are the equipment misused by operators who are not trained properly?
- Are there any compressed air, refrigerant or steam leaks?
- Are there opportunities to tap waste heat from equipment and exhaust gases?
After the energy survey, look at the findings and decide what actions to take. Implement the no-cost or low-cost actions first, such as educating employees, changing habits and practices, proper maintenance of equipment, changing energy settings and removing unnecessary lighting.
Next, consider the higher-cost actions such as installing new energy efficient lighting and equipment, and using energy saving technologies.
Remember to keep the management and employees informed of the energy survey findings, actions taken and energy savings.
Image credit: dlnny; olimohd; lockstockb.



















