Energy Efficient Air Conditioning
Capital Cost vs Carbon Cost -The Challenge for the Future!
At a time when demand for air conditioning is increasing worldwide, the industry is simultaneously confronted by the global imperative for reduced greenhouse gas emission. The ratification of the Kyoto Protocol and a commitment to introduce a Carbon Trading Scheme by the Australian government has put significant pressure on the Air Conditioning Industry to introduce equipment, particularly in the commercial arena, which has significantly reduced energy consumption.
No matter how hard we try we cannot escape the fact that at the other end of the power cable from our air conditioning equipment is a power station pumping huge amounts of CO2 into the atmosphere!
The combination of the need to reduce greenhouse gas emissions and the impact of carbon trading on energy costs will both apply significant economic pressure for increased efficiency, particularly in commercial air conditioning systems.
Without an obvious “new refrigeration technology” to move to, increased energy efficiency is the only short term option for the Australian (and global) air conditioning industry.
With Greenhouse Gas emission reduction targets most likely to be in the order of 25% by 2020 and 50% to 60% by 2050 the air conditioning industry will have to be innovative or face substantial carbon cost penalties. The opportunity for the industry is to actively engage in the greenhouse gas reduction process.
Temperzone is confident that it can achieve energy efficiency improvements of over 30% with existing technology. The increased cost of equipment is easily recovered if an equipment lifecycle model is used, even when calculating energy costs based on current electricity tariffs. If a conservative 15% increase in energy costs is applied over the 15 year lifespan of a new system, to account for the increase carbon cost of electricity under carbon trading, the financial benefits are substantial. (NB: Some Australian projections suggest electricity cost increases of 40%.)
The biggest current impediment to the introduction of energy efficient air conditioning systems is the (short sighted) approach of builders, developers and specifiers to view the air conditioning system only in terms of its initial capital cost, with no regard to the life cycle energy cost or the life cycle carbon cost of the equipment.
With a pay back time of under 2 years the energy efficiency measures are economically viable if a more holistic energy cost perspective is taken.
We are already seeing many companies large and small develop greenhouse gas reduction policies. There will be increasing pressure for energy rating of all commercial buildings and energy efficient (green) premises will ultimately attract premium rents. What we are seeing is a paradigm shift from current capital cost and running cost models to a carbon cost model that will take into account the true cost of energy production. With the advent of a carbon trading system in Australia . energy efficiency will become a key focus of all Australian business.
Temperzone believes it is time for a new approach to Energy Efficient Air Conditioning. It seems obvious that with some fairly simple technological changes we can produce a 30% reduction in energy consumption. At current costs this would cause a 40% increase in capital cost, however, the payback period on the increased cost is only 12 to 18 months. Over the lifetime of the system the reduced energy cost will be in the order of 3 to 5 times the initial capital cost. With increased electricity costs due to carbon trading the saving may be between 4 and 5 times the capital cost. Most importantly the reduction in CO2 emissions is over 35 tonnes per year per unit. See the table below.
| |
Current electricity costs |
15% Increased cost |
40% Increased cost |
| Capital Cost Standard |
$15,000 |
$15,000 |
$15,000 |
| Running cost per year |
$15,000 |
$17,250 |
$21,000 |
| Life cycle in years |
15 |
15 |
15 |
Carbon Cost
The other alternative way of looking at the life cycle cost of the above systems is the actual carbon cost of the system per year. In reality the carbon cost will be taken up in the increased electricity cost.
The other alternative way of looking at the life cycle cost of the above systems is the actual carbon cost of the system per year. In reality the carbon cost will be taken up in the increased electricity cost.
Standard configuration
Approximate annual energy consumption of a 65kw unit (kwh) 120,000
Approximate CO2 emissions from 120,000 kwh (in tonnes) 117.6
Carbon cost (at $40 per tonne) $ 4,704.00
With energy efficient design
Approximate annual energy consumption of a 65kw unit (kwh) 84,000
Approximate CO2 emissions from 84,000 kwh (in tonnes) 82.32
Carbon cost (at $40 per tonne) $3,292.80
Net reduction in CO2 emissions per unit per year (in tonnes) 35.28
The challenge to the industry is to convince government and developers that there is an energy efficient answer that is available now and that if we look at lifecycle costs the savings in both dollars and tonnes of CO2 emissions is substantial.
In future issues we will be looking at specific energy efficiency measures. So watch this space.
