February 24, 2010 - Ultracapacitors or electric double-layer capacitors (EDLCs) fill an important and otherwise vacant niche in the current set of energy storage devices, bridging the gap between batteries and conventional capacitors. They offer greater energy densities than electrostatic capacitors, making them a better choice for back-up applications. They also possess higher power densities than batteries, allowing them to perform a role in load-leveling of pulsed currents. They can help to improve battery performance when combined in hybrid power sources, or they can provide an efficient and long-lasting means of energy storage when used on their own.
According to a recently published report from iRAP, Inc ( www.innoresearch.net), Ultracapacitors for Stationary, Industrial, Consumer and Transport Energy Storage – An Industry, Technology and Market Analysis, the global market for ultracapacitors will grow from an estimated $275 million in 2009 to $725 million in 2014, at an AAGR (average annual growth rate) of over 20% through the forecast period.
There are four major markets where ultracapacitors are needed – stationary, industrial, consumer and transport energy storage power management. Each has its own specific requirements. From 2009 to 2014, transport energy applications, which are mostly automotive applications, will show the highest growth rates, 27.7% AAGR, followed by stationary energy storage at 23.7%, consumer electronics at 22.7% and industrial applications at 14.1%.
The stationary energy storage market needs ultracapacitors for short duration applications of energy storage, which are characterized by the need for high power for short periods of time. These include power quality ride-through applications, power stabilization, adjustable speed drive support, temporary support of DR (distributed resources) during load steps, voltage flicker mitigation and many other applications. UPS (uninterruptible power supply) systems and power management systems used in distributed generation, wind and solar energy generating stations employ a combination battery and ultracapacitor bank whereby the battery is used for long duration interruptions and the capacitor is used for voltage sag support and momentary interruptions. This reduces the cycling duty on the battery, thereby extending its life.
Industrial applications need ultracapacitors to improve power quality, specifically using ultracapacitors to handle power surges and short-term power loss. Since electricity is transmitted at 60Hz or 120Hz, this market also needs high frequency devices based on aqueous electrodes, on a much larger scale
The consumer electronics and computer market needs small high frequency devices in order to reduce battery size. Typical applications are pagers, personal data assistance devices and cell phones. The GSM phone will require a 200Hz response time to improve the transmit burst in a digital phone system. In these devices, high power is more important than energy density. Therefore, to get the desired frequency response, ultracapacitors will use aqueous electrolytes that provide much lower resistance. To attain these frequencies, carbon electrodes need to be thin, with large pores for rapid ion transport through the material.
The transport energy storage market aims to use ultracapacitors as load-leveling devices with batteries in electric and hybrid vehicles. By far the highest value target for ultracapacitor technology is the global automobile industry. Automotive applications range from hybrid drive trains to power network stabilization to the "electrification" of braking, steering, air conditioning and other subsystems to improve the fuel efficiency and reliability of the 50 to 60 million passenger vehicles that roll off assembly lines around the world each year.