What Is Energy Efficiency?

Energy efficiency is both a goal and a condition.

  • More and more energy consumers strive to lower their consumption of energy as part of their daily activities.
  • At the same time, energy efficiency describes a state in which the amount of energy consumed is reasonable in relationship to the activities being supported.

When energy resource is cheap consumers do not dwell on efficiency.   Moreover, if achieving efficiency is expensive most consumers will not invest in ways to reduce energy consumption at any cost.   The only exception is for those who aim to reduce energy consumption for other reasons such as avoiding adverse environmental impacts.

At the same time, when prices are high – or when they are volatile and so risk impacting budgets even when prices are low – efficiency attracts more attention.

Sources of Inefficiency

Understanding the aims of efficiency requires recognizing where energy is lost.  Typical sources of loss are:

  • Leakage. Buildings are notoriously inefficient and uninsulated and often lose over 30% of their heating and cooling through uninsulated walls, attics, corner studs and windows.
  • Distribution loss. Energy lost along transmission or distribution lines and heat lost along, say, water pipes.
  • Standby losses. Examples include water tanks that keep reservoirs of water heated when there is no demand.
  • Inefficient engines. Furnaces and machinery often operate at less than 80% efficiency with the balance lot through heat.
  • Incandescent light bulbs and CFLs give off heat which not only reduces the amount of light but may require additional air conditioning to offset the impact on interiors.  Old magnetic ballasts for fluorescent lights use far more energy than electronic ballasts.
  • Firing up. Motors and compressors that waste energy when firing up.

Strategies for Improving Efficiency

There are many affordable solutions for reducing energy consumption.  Some such as lighting upgrades require modest capital outlays; others such as furnace upgrades may be expensive but will yield immediate savings in energy consumption.   Qualified advisors can help consumers understand which solutions are most cost-effective.

Examples of energy efficiency solutions are listed below.  All of these are proven technologies.

  • Cogeneration. A Sterling engine is used to generate heat while producing electrons and free electricity in an electromagnetic field.
  • Battery Storage. Batteries, recently affordable, are capable of storing solar energy produced in peak hours in excess of real time needs and releasing it in off-peak, or alternatively storing energy during off-peak hours for release during peak hours.
  • Furnace upgrades. The efficiency of many modern furnaces approach 90%, some 10-20% better than furnaces as little as 10 years old.
  • Insulation. Modest investments in insulation can reduce consumption by 30% or more, yielding immediate cost savings benefits.  An infrared camera or a blower door test in residential and commercial spaces can quickly identify leaks in building frames, roofs and windows.
  • Lighting. LEDs (light emitting diodes) and CFLs (compact fluorescents) reduce energy consumption dramatically for a modest up front cost.
  • Tankless or Demand Water Heaters. These water heaters fire up with electricity or propane only when there is a call for hot water.
  • Solar Thermal. Solar panels heat a glycol mixture that circulates to a water tank and can heat a reservoir of water over 150° Fahrenheit.
  • Submetering. Submetering can be used to track energy consumption and detect inefficient usage in comparable locations.

Auditing Consumption

An audit of energy consumption and bills is used to determine whether an energy consumer can benefit from energy efficiency solutions.   An objective audit is a wise first step before engaging or soliciting contractor bids.

A number of companies conduct these audits.  In retaining an auditing firm a consumer should confirm that the firm is familiar with the wide range of potential solutions and does not promote only one or a handful of technologies.  Moreover, any engagement should be clarify the consumer’s objectives, the scope of the consultant’s work, and the cost of the consultant.