Monday, April 23, 2012

Viable Alternative Energy Reduction Methods

There is no doubt that one of the biggest challenges facing the World today is the task of reducing our dependence on fossil fuels, and reducing harmful emissions into the Earth’s atmosphere.   Most Governments look towards heavily subsidising Photovoltaic (PV) Solar Panels as a way of achieving this goal however there are other ways that possibly could be considered as a priority over PV Solar in order to achieve higher energy reductions for less cost.  The use of energy efficient Heat Pump heating and cooling products, particularly for larger commercial or industrial installations can produce substantial energy savings at a much lower cost but with a similar saving in energy that is achieved with Solar PV Panels.   The current disadvantage with Solar PV is the overall efficiency of the panels (generally between 17% and 18%) to collect available Solar energy when the sunlight is available.   On a good clear day this still only represents approximately 33% of each 24 hour period and that is an additional drawback associated with Solar PV Panels.
 

In small installations, for a similar capital investment, energy efficient Heat Pump heating and cooling products can more than double the actual energy reduction achieved when compared to Solar PV Panels.   For larger installations such as Hotels, Hospitals, Processing Factories, and other similar places the reduction in energy can be even higher if energy efficient Heat Pump heating and cooling products are used.  The purpose of giving strong consideration to the Heat Pump method is that they will create a much larger reduction in energy load requirements from the main generating facility which can be achieved quickly, easily and at a much lower cost.   Because Heat Pump heating and cooling products substantially reduce the energy load from the generating facility they therefore achieve the first stage of being energy independent by reducing the need to augment existing, or build new generating facilities to service the needs of the ever expanding population.
 

If Governments were to consider providing the same level of subsidy that is available for Solar PV Panels and use that to subsidise large Heat Pump heating and cooling products then they could quite easily achieve a much higher Return on Investment (ROI) for any funds invested.   Solar PV Panels can still be used as an energy reduction alternative, but in the early stages of working towards this goal it may be more beneficial to give a higher priority to energy efficient products such as Heat Pumps that can provide an immediate and high impact to energy reduction for the same level of investment, but with a significantly improved ROI.
By
Mel Peatey.

Thursday, April 12, 2012

Typical Air to Water Heat Pump Cycle

The heat pump operates on the basis of a working fluid (refrigerant/coolant) which changes state (liquid/gas) in a continuous cycle and absorbs and releases heat.
The heat pump cycle is essentially based on the Carnot cycle. (Theoretical thermodynamic cycle proposed by French Physicist & Engineer Nicolas Léonard Sadi Carnot in 1824)
Heat pump heating/cooling circuit is shown below:
 

The diagram illustrates the operation of the heat pump cycle:



The Importance of Heat Pump Design


To achieve the best economical benefits from the installation of Heat Pump water heaters, the design is critical.   For domestic installations there is a little more flexibility because daily hot water volume requirements are considerably lower than those required in commercial or industrial applications, and therefore a more general approach can be made to selecting the most suitable domestic system.  However for the larger and more continuous daily volume requirements for commercial or industrial applications, a suitably designed Heat Pump water heater is critical in order to achieve the most economically suitable outcome.  The most important issue with the larger volume installations is firstly that the designed system must be able to – do the job that is expected of it and that is, to provide hot water at the fixture point at any time of the day and on any day of the year.