Choosing active solutions for power management

Reduced energy costs are accomplished in a variety of ways. One solution is supply side management, which reduces costs through utility rate structure optimization, load aggregation, penalty avoidance and bill verification. These methods do not reduce energy consumption but, instead, ensure that energy is consumed using the provider’s lowest cost of energy.

07/01/2009


Reduced energy costs are accomplished in a variety of ways. One solution is supply side management, which reduces costs through utility rate structure optimization, load aggregation, penalty avoidance and bill verification. These methods do not reduce energy consumption but, instead, ensure that energy is consumed using the provider’s lowest cost of energy.

The second technique modifies the process to consume energy more efficiently. Methods include using adjustable frequency drives instead of using valves or dampers; using higher efficiency motors, pumps, transformers or changing process configurations such as using new boiler control algorithms; maintaining a compressed air leak management program; capturing and reusing waste heat; or improving vessel or building insulation.

A third energy reduction cost technique uses measurement systems to track production of a process, measure the ratio of production quantity to energy consumption and trend this ratio as a process efficiency and compare this value to best case efficiency benchmarks. As is done with statistical process control and statistical quality control, deviations from baseline identify when process efficiencies are declining.

Active load management

Using active load management allows users to cut energy costs by reducing the number or types of loads connected to the source of power or by shifting the energy consumption to a lower cost time period. Active load management seldom makes sense unless the total costs associated with reducing or shifting loads to another time period are more than offset by savings from a reduction in energy cost from that load change.

Reducing load almost always implies reducing output, at least for a certain time window, but it also can involve shifting the energy use to a more advantageous time %%MDASSML%% a time when energy costs are lower. A well thought out return on investment analysis on a load shed/load shifting system includes not only those reduced energy costs, but must include costs associated with installation of any equipment to perform the load reduction, including the new costs associated with maintenance of the system after this new load management is implemented. You may find that the increased maintenance costs for the new load reduction system are more than offset by the lower maintenance costs associated with the less frequently or less heavily loaded equipment, resulting in longer life of the equipment. Longer equipment life lowers long term capital requirements to operate a process.

Examples of active load management are practically endless, but include: