Energy Saving Scams And Mis Representations
There are many energy saving schemes promoted in the industry today, some of these work, but many either can not work, or can not work in the manner that they are promoted.
In order to reduce energy consumption, there must first be energy wasted, and second, a means of reducing that energy wastage.
You can only save a portion of the energy that is being wasted.
If you are serious about saving energy, you must:
Energy wastage generally occurs due to either reduced operating efficiency, or excessive output.
For example, an office is provided with lighting sufficient to light the work areas at night. As the ambient light level is increased, (day time) the supplemental lighting levels required, are reduced, but so often, the full light output is used irrespective of the ambient light levels. The artificial light levels can be reduced, or in some cases totally removed without greatly affecting the light levels at the work area.
It is important that in reducing the energy consumed, you do not reduce the "work" output to a level that it begins to impact on the productivity of the plant. Lighting can often be reduced during the day, pumps and fans can be slowed down when there is reduced flow required.
Energy saving is more commonly related to process control, than to "magic" add on boxes.
Typical add ons for saving energy:
Nola type energy savers for induction motors. - These will save energy if the motor is operating at very light load and is operating inefficiently. Larger and more modern motors are far more efficient than old small motors. There are some applications for saving energy using this technology, but they are very limited.
Motors must be small, operate under very light load for very long periods of time.
Power factor correction. - Power factor correction is a means of reducing the current drawn by an inductive load. This will reduce the line losses in a transmission system, but will have little or no impact on the KWHr meter except where the mater is installed many KM from the connected load and the correction is applied at the connected load.
In the industrial installations, there are usually electricity tarriffs based on KWHrs plus an additional surcharge for poor power factor, or a KVA maximum demand penalty or similar. Money can be saved by a reduction in the penalty, not the reduction in KWHrs.
In the domestic installation, the power is charged for KWHrs used. There is no power factor penalty or KVA maximum demand penalty. There is no financial gain from the addition of power factor correction in the domestic environment.
Lighting Controllers. - Lighting controllers that reduce the level of artificial light during periods of high ambient lighting, will achieve appreciable energy savings. Some controllers permanently reduce the voltage to the lamps, reducing the light output under all conditions. These will reduce the energy saved, but will also reduce the usefulness of the lighting when it is required most.
Variable Speed Controllers. - VSDs can be used to control the speed of a machine. There can be significant energy reduction if the machine is slowed down when it does not need to operate at full speed. For example, pumps operated so that they run at a speed dependent on the flow requirements will reduce the cavitation losses in the pump. If the pump is required to run at constant full speed, the addition of a VSD will actually waste another 5% of energy.
In order to reduce energy consumption, there must first be energy wasted, and second, a means of reducing that energy wastage.
You can only save a portion of the energy that is being wasted.
If you are serious about saving energy, you must:
- Establish where energy is being wasted.
- Determine how much energy is being wasted
- Determine possible means of reducing the wastage
- Determine the amount of reduced wastage
- Determine the cost and viability of reducing the wastage
Energy wastage generally occurs due to either reduced operating efficiency, or excessive output.
For example, an office is provided with lighting sufficient to light the work areas at night. As the ambient light level is increased, (day time) the supplemental lighting levels required, are reduced, but so often, the full light output is used irrespective of the ambient light levels. The artificial light levels can be reduced, or in some cases totally removed without greatly affecting the light levels at the work area.
It is important that in reducing the energy consumed, you do not reduce the "work" output to a level that it begins to impact on the productivity of the plant. Lighting can often be reduced during the day, pumps and fans can be slowed down when there is reduced flow required.
Energy saving is more commonly related to process control, than to "magic" add on boxes.
Typical add ons for saving energy:
Nola type energy savers for induction motors. - These will save energy if the motor is operating at very light load and is operating inefficiently. Larger and more modern motors are far more efficient than old small motors. There are some applications for saving energy using this technology, but they are very limited.
Motors must be small, operate under very light load for very long periods of time.
Power factor correction. - Power factor correction is a means of reducing the current drawn by an inductive load. This will reduce the line losses in a transmission system, but will have little or no impact on the KWHr meter except where the mater is installed many KM from the connected load and the correction is applied at the connected load.
In the industrial installations, there are usually electricity tarriffs based on KWHrs plus an additional surcharge for poor power factor, or a KVA maximum demand penalty or similar. Money can be saved by a reduction in the penalty, not the reduction in KWHrs.
In the domestic installation, the power is charged for KWHrs used. There is no power factor penalty or KVA maximum demand penalty. There is no financial gain from the addition of power factor correction in the domestic environment.
Lighting Controllers. - Lighting controllers that reduce the level of artificial light during periods of high ambient lighting, will achieve appreciable energy savings. Some controllers permanently reduce the voltage to the lamps, reducing the light output under all conditions. These will reduce the energy saved, but will also reduce the usefulness of the lighting when it is required most.
Variable Speed Controllers. - VSDs can be used to control the speed of a machine. There can be significant energy reduction if the machine is slowed down when it does not need to operate at full speed. For example, pumps operated so that they run at a speed dependent on the flow requirements will reduce the cavitation losses in the pump. If the pump is required to run at constant full speed, the addition of a VSD will actually waste another 5% of energy.
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