CHAPTER 1
Introduction
What is energy analysis?
Energy analysis / Energy systems analysis = the
study of energy use, energy production and energy
conversion in society
• It is an attempt to explain historic developments of
energy use and energy production, to explore
possible future developments, and to consider
how such developments can be influenced
Energy Systems
• consists of a number of stages from the extraction
to the end use of energy
• energy services can be met by various sorts of
equipment with different energy inputs
- Schematic representation of a simple chain from
extraction to end use within an energy supply system
Energy and Society
• Developments in society influence the energy
system in many ways, but the energy system also
affects society
Energy and Human Development
• Energy is critical for human development. Energy
is needed for sufficient food supply and the
preparation of healthy food, as well as for heating
and lighting
• Energy is also needed for other important
preconditions for development: water supply,
health care, and education.
• One may expect that increasing GDP as a result of
increasing activity will lead to higher energy use.
However, the relation between the two quantities
is not proportional.
There are two key reasons for this;
1. economic activities differ in how much energy
use is needed for a certain contribution to GDP
2. The second reason is energy efficiency. Energy
efficiency improvement leads to a reduction of
energy use per unit of activity
• Differences in energy efficiency also partly explain
the differences in energy use per capita among
developed countries,
• One of the reasons for this is that energy
efficiency is often worse in the USA, e.g. steel
companies use more energy per tonne of steel,
and cars use more gasoline per km driven than in
the UK and Japan.
Environmental impacts on energy use
Climate Change - most important environmental
problem associated with energy production and use
• The combustion of all fossil fuels leads to the
formation and emission of carbon dioxide (CO2).
• About half of the CO2 is absorbed by the oceans
and the biosphere, but the remainder leads to an
increased concentration of CO2 in the atmosphere
• The sun sends radiation energy to the Earth, most
of the energy in the range of visible light
• The incoming radiation is partly reflected (by the
Earth’s surface and clouds), but it is to a large
extent absorbed by the Earth’s surface
• The Earth also radiates energy - but due to the
relatively low temperature at the Earth’s surface, this
is mainly in the form of infrared radiation
• The temperature at the Earth’s surface is such that
incoming and outgoing radiation are in equilibrium
• Carbon dioxide molecules in the atmosphere absorb
infrared radiation, and after absorbing it, emit the
energy again in all directions, part of it back to the
Earth’s surface, thereby reducing the amount of
energy that radiates back into space
• So, an increased concentration of CO2 leads to a
higher amount of incoming radiation towards the
Earth’s surface
• Greenhouse Effect = As the ingoing and outgoing
radiation needs to be in balance, a new equilibrium
will be formed: the higher flow of outgoing radiation
will be attained at a higher surface temperature,
making the Earth warmer.
• Gases that show absorption in the infrared spectrum
and cause the mechanisms described here are
called greenhouse gases
• water vapour is the most important natural
greenhouse gas, and without water vapour in the
atmosphere, the temperature on Earth would be
substantially lower.
• Ozone (O3), methane (CH4), and nitrous oxide
(N2O) are also greenhouse gases and their
concentrations are increasing as a result of human
activities
• climate system is very complex
• important positive feedback = through water vapour:
an increased temperature of the atmosphere leads to
an increased presence of water vapour in the
atmosphere, which adds to the strength of the
greenhouse effect
Since 1880, the average temperature on Earth has
increased by about 1.0 °C.
It is expected that without measures to limit and reduce
emissions, the average global temperature will likely
increase by over 3–4 °C by the end of this century
compared to pre-industrial levels.
impacts of climate change:
1. droughts and water shortages, especially in regions
that are already vulnerable
2. regional decreases in food production
3. deterioration of ecosystems that cannot adapt
rapidly enough to the changing climate
4. spread of diseases, like malaria, to areas where
they did not occur before
5. sea level rise, due to expansion of sea water and
melting of pack ice and glaciers
6. an increase in the number of extreme weather
events, such as hurricanes
At temperatures higher than 1,400 °C oxygen in the air
begins to dissociate, leading to the following reactions;
N2 +O = NO+ N
NO2 = NO + O
Furthermore, the presence of hydroxyl radicals (OH)
adds to NO formation:
N + OH = NO + H.
• The net effect is the formation of NO out of air
• The NO oxidises further to NO2, partly during
combustion, but mainly in the atmosphere
• SO and NO are often emitted from high chimneys and
can be transported over long distances, so this is a
problem with a continental character
• In an aqueous environment, the H+ ions are
separated off, leading to the well-known acidification
of lakes and soil
• The degree of acidification of soil depends on the
soil’s buffer capacity
2
• to avoid the most dangerous impacts of climate
change, it is necessary to limit global average
temperature increase to a maximum of 1.5–2 °C
• man-made greenhouse gas emissions need to be
reduced to net zero in the second half of this century
Acid Deposition - caused mainly by emissions of
sulphur dioxide and nitrogen oxides from burning fossil
fuels
• compounds will react with water in the atmosphere
(or in the soil) and form acidic substances that can
damage forests, lakes and ecosystems
• Emissions of sulphur dioxide and nitrogen oxides
result from both natural sources, such as volcanoes,
and human activities, primarily from fossil fuel
combustion
• Many fossil fuels contain sulphur
• sulphur content of coal can be 1–5 percent, and
crude oil also contains several per cent sulphur
• When the fuel is combusted, the sulphur is converted
to gaseous sulphur dioxide (SO2) which is emitted to
the air
• Nitrogen oxides (NO and NO2, together referred to
as NOx) can be formed out of nitrogen compounds
also present in the fossil fuels (mainly in coal)
• However, more important is the so-called thermal
NOx formation.
• It negatively impacts human health.
• Note that in contrast to this, stratospheric ozone is
desirable as it shields the Earth’s surface from highintensity ultraviolet radiation.
• coal contributes the most to emissions per unit of energy
used
• mainly due to the inherent properties of coal, namely its
high sulphur and ash content. Among the different end-use
sectors, transportation accounts for the highest contribution
to emissions
• Emission control measures have strongly reduced
emissions in many industrialised countries
x
impacts of acidification:
1. loss of nutrients in soils
2. release of harmful substances from the soil (like
aluminium, cadmium, lead, copper, and zinc)
3. reduction of ecosystem variability and biodiversity
4. direct impacts on plant vitality through stoma
damage
• emission of sulphur dioxide can be prevented through
the use of low-sulphur coal, fuel desulphurisation
Air Pollution - combustion of fossil fuels leads to a
number of emissions that affect human health
• particulate matter
• sulphur dioxide (SO2)
• nitrogen oxides (NO and NO2)
• carbon monoxide (CO)
• ozone (O3): an air pollutant which forms through a
photochemical reaction from nitrogen oxides and
volatile organic compounds (hydrocarbons). This is
so-called tropospheric ozone, the ozone present in
the lower levels of the atmosphere.
World Health Organisation (WHO) for particulate matter are
as follows:
Annual mean: PM10 less than 20 µg/m3
PM2.5 less than 10 µg/m3
24-hour mean: PM10 less than 50 µg/m3
PM2.5 less than 25 µg/m3
• In many cities these values are still exceeded
• The biggest air pollution problems, however, occur in large
cities in developing countries
• In many of these cities, the WHO guidelines are exceeded
by a factor ten or
• more
There are a number of causes for this:
1. limited adoption of pollution control technology
2. cars and equipment are often old and maintenance is
poor
3. the small-scale use of coal and wood is still common
Other Impacts:
impacts of energy production and use:
1. accidents with oil transport, leading to oil spills at
sea
2. local depletion of wood resources
3. regional impacts of hydropower
4. waste from the fossil fuel cycle, including slag
and fy ash from coal combustion
5. accidents caused by unsafe nuclear power
plants and possible discharges of radioactive
waste from the nuclear fuel cycle
6. disturbance and pollution caused by mining coal
and uranium
7. pollution of underground water resources due to
fossil fuel production
8. micro-seismicity events as a result of fossil fuel
exploitation
9. water shortages or high river temperatures
resulting from water use
Security of energy supply
Access to energy
• Much of the world’s population lacks adequate energy
resources to serve their basic needs
• most of the people suffering from a lack of access to
sufficient energy live in developing countries, ‘fuel
poverty’ also occurs in the industrialised world
• Fuel poverty differs from country to country but it is
often the people with the lowest income that do not
have the ability to
• for example, insulate their homes adequately or buy
energy-efficient equipment
• This can be due to lack of knowledge or financial
resources, and it may lead to high energy costs,
discomfort, running up debts, and ultimately to natural
gas and electricity shut-offs
Global supply of energy sources
• nineteenth century, when production of crude oil had
just started, there were already warnings about a
potential depletion of oil reserves
• Since then, there has always been concern about the
future depletion of resources
• the concept of peak oil was introduced: the
assumption that depletion of reserves currently in
production outpaces the development of new
production sites
• This would mean that we are close to reaching the
peak of oil production
• global fossil fuel reserves are limited
• there has always been technical progress in energy
production technology, more efficient use of energy
products and substitution of the resources that are
most scarce
• Example; in the case of oil we have seen horizontal
drilling, which makes better resource utilisation
possible; much more efficient passenger cars; and the
shift to coal and natural gas in the power sector
• we need to reduce greenhouse gas emissions to net
zero in the second half of this century
Geopolitical concerns
• The total global availability of energy is one thing; the
distribution across regions is another.
• crude oil, natural gas, and to some extent uranium are
distributed unevenly across the globe
Example;
• A more recent event is the threat of the disruption
of natural gas supply from Russia to Ukraine
• Since 2005 there have been disputes over natural
gas prices and debt payments between these
countries
• As a result, Russia has regularly cut off natural
gas supply to Ukraine
• As most of the natural gas exports from Russia to
Central Europe flow through pipelines through
Ukraine, this also threatens natural gas supply to
these countries.
• Actual supply disruptions occurred in several
countries in Central Europe in January 2009.
Energy and Sustainable Development
sustainable development - is a ‘development that
meets the needs of the present generations without
compromising the ability of future generations to
meet their own needs’
• takes into account economic, social, and
ecological aspects
• also consider social and environmental goals:
people, planet, and profit
• Resource depletion and the possibility of climate
change and other environmental impacts may
seriously affect the capability of future generations
to meet their own needs
Results;
1. ensure universal access to modern energy
services
2. double the global rate of improvement in energy
efficiency
3. double the share of renewable energy in the
global energy mix
It is important to note that the two targets set out in
the definition may be conflicting:
1. development for the present generation may
require more energy, which can lead to higher
environmental impacts
2. a reduction of the quality of life for future
generations
A way out of this potential conflict – as already set
out by the World Commission on Environment and
Development – is a combination of renewable
energy technologies, and efficient use of energy
• large group of scientists has carried out an
extended assessment of the future of the global
energy system: the Global Energy Assessment
(GEA).
• They conclude that there are four major
challenges to sustainability of the energy system
and have defined aspirational goals for each of
these
• As a result of their assessment, they conclude that
energy systems can be transformed to support a
sustainable future, but that an effective
transformation requires immediate action
• They also stress the importance and opportunities
of both energy efficiency and renewable energy.
• Included in the Sustainable Development Goals
(created by UN in 2015)
• principles for the international development
agenda up to 2030.
• As one of the 17 goals, the SE4All objectives are
summarised as: ‘ensure access to affordable,
reliable, sustainable and modern energy for all’.
• Paris Agreement; (created December 2015)
Agreement on climate change
• Countries have agreed that average global
temperature increase should stay well below 2 °C
and to pursue efforts to limit the increase to 1.5
°C.
• sustainable development has become the key
target in energy policy making and also
increasingly in business strategy development