When generating
hydropower
Hydropower (from Ancient Greek -, "water"), also known as water power or water energy, is the use of falling or fast-running water to Electricity generation, produce electricity or to power machines. This is achieved by energy transformation, ...
, the head is the distance that a given water source has to fall before the point where power is generated. Ultimately the force responsible for hydropower is
gravity
In physics, gravity (), also known as gravitation or a gravitational interaction, is a fundamental interaction, a mutual attraction between all massive particles. On Earth, gravity takes a slightly different meaning: the observed force b ...
, so a
hydroelectric
Hydroelectricity, or hydroelectric power, is Electricity generation, electricity generated from hydropower (water power). Hydropower supplies 15% of the world's electricity, almost 4,210 TWh in 2023, which is more than all other Renewable energ ...
ity plant with a tall/high head can produce more power than a similar plant with a short/low head. In short, for a given water flow, a larger head will be converted into greater
kinetic energy
In physics, the kinetic energy of an object is the form of energy that it possesses due to its motion.
In classical mechanics, the kinetic energy of a non-rotating object of mass ''m'' traveling at a speed ''v'' is \fracmv^2.Resnick, Rober ...
. That energy is then harnessed by a
water wheel
A water wheel is a machine for converting the kinetic energy of flowing or falling water into useful forms of power, often in a watermill. A water wheel consists of a large wheel (usually constructed from wood or metal), with numerous b ...
or
water turbine
A water turbine is a rotary machine that converts kinetic energy and potential energy of water into mechanical work.
Water turbines were developed in the 19th century and were widely used for industrial power prior to electrical grids. Now, t ...
to create usable hydropower.
Fabrics
Hydrostatic head is also used as a measure of the waterproofing of a fabric, commonly in clothing and equipment used for
outdoor recreation
Outdoor recreation or outdoor activity refers to recreation done outside, most commonly in natural settings. The activities that encompass outdoor recreation vary depending on the physical environment they are being carried out in. These activitie ...
. It is measured as a length (typically millimetres), representing the maximum height of a vertical column of water that could be placed on top of the fabric before water started seeping through the weave. Thus a fabric with a hydrostatic head rating of mm could hold back a column of water five metres high, but no more.
Notes
{{reflist
See also
*
Hydraulic head
Hydraulic head or piezometric head is a measurement related to liquid pressure (normalized by specific weight) and the liquid elevation above a vertical datum., 410 pages. See pp. 43–44., 650 pages. See p. 22, eq.3.2a.
It is usually meas ...
for a more technical description of the physical principle of hydraulics
*
Tent
A tent is a shelter consisting of sheets of fabric or other material draped over or attached to a frame of poles or a supporting rope. While smaller tents may be free-standing or attached to the ground, large tents are usually anchored using g ...
and
waterproofing
Waterproofing is the process of making an object, person or structure waterproof or water-resistant so that it remains relatively unaffected by water or resists the ingress of water under specified conditions. Such items may be used in wet env ...
, as hydrostatic head is used as a measurement of waterproofness
References
U.S. Bureau of Reclamation: Glossary(See “Head”)
(See “Hydraulic head”]
Society of Petrophysicists & Well Log Analysts: Glossary(See “Hydraulic head”)
Hydrology