December 21, 2013

Inverter AC: The future of HVAC industry

The time has far gone when the AC was considered a luxury, today AC is as much as a need as an smartphone ah! maybe less then a smart phone bu...t; nerveless  nobody can deny that the AC has become a necessity. 

With increasing use of AC's the need of energy efficient systems is also arising which drive the research community and market both into some real  R&D work and we may safely presume that inverter technology is the outcome of some serious R&D stuff.


What really is an inverter AC and why its more efficient?

An inverter AC is an AC which obviously and essentially contains an inverter which control the speed of compressor in accordance to the varying load conditions.

NO the inverter AC is not more efficient, it's just save some power And the third affinity law explain the power saving property of the system witch says


power is proportional to the change in speed cubed


In an inverter Air Conditioner, compressor is driven by a DC motor and an inverter is used to control the speed of the compressor motor, which allows it to change the capacity as per the set point temperature of the Air Conditioner and outdoor weather conditions. This feature helps cut down the electricity consumption of the Air Conditioner, and is the biggest difference between a non-inverter Air Conditioner and an inverter Air Conditioner.
The compressor motor of a non-inverter Air Conditioner either operates at a maximum capacity, or is switched off. This leads to unnecessary electricity consumption and higher electricity bills.

The ability of an Inverter Air Conditioner to control the speed of the compressor motor eliminates stop-start cycles. This in turn makes the Air Conditioners less prone to breakdowns and cheaper to run.

Does Inverter AC  always save energy over conventional constant volume AC?

There are certain conditions in which inverter AC cannot simply give the its best but before going to that we must first understand that an inverter AC has some extra components in it which all consume some energy (no component is 100% efficient) so if we compare two similar machines literally we will see that the normal AC is better in the leaflets of tech specs. but in operation the story is otherwise(well it actually depends on the load condition)

   

 Here are the results of an study where a inverter AC and a constant volume AC were tested in varying load conditions in real time operation

      Inverter system does not have “ON-OFF cycles” which increases the life of the systems as compared to the constant volume systems.
Inverter systems meet the zone set point without significant fluctuations in the zone temperature whereas in constant volume system fluctuations of ±2 0C were observed.
Inverter AC only gives energy saving at part load conditions, therefore Inverter technology must be used only where the AC runs most of the times at part load conditions.
In Inverter systems electric load only changes when heat load on the system changes and load profile does not fluctuate. Whereas in a constant volume system there is frequent variation in the electric demand load due to its ON OFF cycle operation.
Inverter technology is emerging as the energy saving technology but its energy saving capability largely depends on the time span when it operates at part load.
When working at full load Inverter system does not work as energy saving option, therefore caution must be taken with application of Inverter systems.

December 15, 2013

Decentralized Power Generation: is it the solution ???

We relay on he centralized grid for all our electricity requirement but in the recent past due to uncertain availability of grid electricity we are also looking for the ways of reducing our dependency on the central grid and solutions like backup  inverters and backup generates are emerging.

But the grater question is, are we moving towards a scenario of decentralized power generation? 

Well it is not unlikely and in the current era where we have a lot of options of clean power generation ie solar, wind, biomass, geothermal, tidal, hydro and they all can serve as a source for decentralized generation.
Solar Photovoltaic and biomass are the most promising options of all in Indian context. solar PV can easily satisfy all the needs in both urban and rural areas in the form of roof top personal generation units or a community solar plant. whereas biomass can address all the low grade energy as well as can serve as the fuel foe electricity generation.

The future scenario of energy generation can be seen where every man is for himself, maybe its too far fetched to say this but we certainly moving on this path even if the speed is of the tortoise or is it of an ice berg,s speed well i cant say for sure...