Glossary
The following definitions reflect those used by the International Energy Agency (IEA); definitions used by other organisations and publications may vary.
H2
hydrogen
H20
water
HAPs
hazardous air pollutants
HC
hydrocarbons
HDI
Human Development Index
HDV
heavy-duty vehicle
HDVC
high voltage direct current
HFCV
hydrogen fuel cell vehicle
HFO
heavy fuel oil
hi NUC
high nuclear scenario (in IEA modelling and publications)
hi REN
high renewables scenario (in IEA modelling and publications)
HLW
high-level waste
HPI
Human Poverty Index
HSPF
heating seasonal performance factor
HSR
high-speed rail
HTS
high temperature superconductor
HVAC
heating, ventilation and air conditioning
HVC
high-value chemical
HVDC
high-voltage direct current line
hard coal
coal of gross calorific value greater than 5 700 kilocalories per kilogramme on an ashfree but moist basis. Hard coal can be further disaggregated into anthracite, coking coal and other bituminous coal.
heat
In IEA energy statistics, heat refers to heat produced for sale only. Most heat included in this category comes from the combustion of fuels, although some small amounts are produced from geothermal sources, electrically powered heat pumps and boilers.
heat energy
Heat is obtained from fuels combustion, nuclear reactors, geothermal reservoirs, capture of sunlight, exothermic chemical processes and heat pumps which can extract it from ambient air and liquids. It may be used for heating or cooling or converted into mechanical energy for transport vehicles or electricity generation. Commercial heat sold is reported under total final consumption with the fuel inputs allocated under power generation.
heavy petroleum products
heavy petroleum products include heavy fuel oil.
hedge funds
an investment fund opened to a limited range of investors. These funds aggressively manage a portfolio of investments that use advanced investment strategies such as leveraged, long, short and derivative positions with the goal of generating high returns.
Human Poverty Index
measures life expectancy at birth, adult literacy and & school enrolment, and per-capita GDP (adjusted for purchasing power parity [PPP]). HPI-1 is a modified HPI for developing countries that measures probability at birth of not surviving to 40, adult literacy, % of population without clean water and % of children underweight.
hydro
the energy content of the electricity produced in hydropower plants assuming 100% efficiency.
hydropower
the electrical energy derived from turbines being spun by fresh flowing water. This can be from rivers or from man-made installations, where water flows from a high-level reservoir down through a tunnel and away from a dam. For more information, click here.
Ha
hectare (10 000 m2)