Wind energy storage technologies - Wind Power Generation and Wind Turbine Design - page 694

to a large wind turbine and Norsk Hydro is continuing a project to provide Utsira
Island with a wind hydrogen system. In Germany, Siemens and P&T Technologies
are developing a wind hydrogen engine using an ICE. In the UK Wind Hydrogen
Limited intend to develop large-scale wind hydrogen schemes. Finally, HyGen in
California is developing a multi megawatt hydrogen generating and distributing
network [ 2 ].
Car manufacturers are driving research in hydrogen for both the transport and
infrastructure divisions. The automotive industry has engaged in setting up a strat-
egy for the introduction of hydrogen to the transport sector with a number of single
prototype projects advancing to fl eet demonstrations [2]. Hydrogen is a serious
contender for future energy storage due to its versatility. Once hydrogen can be
produced effectively, it can be used for practically any application required.
Consequently, producing hydrogen from renewable resources using electrolysis is
currently the most desirable objective available. Primarily due to the versatility
and potential of hydrogen to replace conventional fuel, “it is envisaged that the
changeover to a hydrogen economy is less than 50 years from now” [2].

4.10 Thermal energy storage

Thermal energy storage (TES) involves storing energy in a thermal reservoir so
that it can be recovered at a later time. A number of thermal applications are used
instead of electricity to provide heating and cooling including aquifer thermal
storage (ATS) and duct thermal storage (DTS). However, these are heat genera-
tion techniques rather than energy storage techniques and therefore will not be
discussed in detail here. In terms of storing energy, there are two primary TES
options. The fi rst option is a technology which is used to supplement air condition-
ing in buildings and is displayed in Fig. 18. The second option is an energy storage
system rather than a technology which will be discussed in more detail later.

Standard Building Cooling System
Without ACTES

Standard Building Cooling System
With ACTES

Chiller Chiller

Cooling Load Cooling Load

Water/Ice Storage

Figure 18: Air-conditioning thermal energy storage setup [ 3 ].