The document discusses trends in global energy consumption and renewable energy. It notes that while global energy consumption has been rising, there is a shift toward renewable sources like hydro, wind, solar and bioenergy. Country-level trends vary significantly based on economic growth and policies supporting renewable energy. The future outlook suggests renewable sources will continue growing to meet energy demands while reducing environmental impacts from traditional fossil fuels.

1. RENEWABLE ENERGY
A CRITICAL REVIEW
Charles Isiadinso
February 10, 2015
Contents
1 INTRODUCTION 2
2 TRENDS 2
2.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2.2 Transportation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.3 Domestic Consumption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.4 Industry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3 RENEWABLE ENERGIES 4
3.1 Hydro . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.2 Wind . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.3 Solar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.4 Bioenergy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4 ENERGY PRODUCERS & CONSUMERS 6
4.1 Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
4.2 Future . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
5 ENVIRONMENTAL IMPLICATIONS 6
6 AUTOMOTIVE INDUSTRY 8
7 Developing World 9
1

2. 1 INTRODUCTION
Over the past 10 years, global energy consumption has been increasing, as shown in figure 1a; and consump-
tion is expected to keep growing, by up to 41% by 2035[15], if nothing is done to control it. Global energy
is produced from crude oil, coal, natural gas, nuclear and renewable sources such as wind, hydro, solar etc.
Energy consumption can be broken down by source, as shown in figure 1b, with over 12000 terawatt-hours
(TWh) from crude oil, coal and natural gas each, and under 5000 from water, nuclear and other renewable
sources (e.g. wind, solar etc.)
(a) [1]
(b) [2]
Figure 1
Demand for energy has social, technological, political, economic and environmental implication, both in the
short and long terms, in developing and developed countries. For example, in 2004, China’s GDP was 1904[3]
(billion 2000$) and energy consumption was 2094[3] (TWh), but by 2012, GDP had grown by 149.79% to
4756[4] (billion 2000$) and energy consumption had reached 4737[4] (TWh); a 126.2% growth. While, in the
same period, Japan had a 4.83% fall in GDP and a 4.1% fall in energy consumption.
2 TRENDS
2.1 General
Generally, from 2000, global energy consumption rose steadily, but in 2011, as a result of global economic
crisis, energy consumption in the G20 slowed down significantly[5], figure 2 below shows consumption by county
from 2000 to 2011. Economic growth in China and other rapidly developing markets, have pushed global energy
consumption up year after year. The Middle East, between 1990 and 2008, saw a 170% increase in energy
consumption, Africa and Latin American saw 70% and 66%, in the same period, respectively, while USA and
the European Union (EU) saw 20% and 7% respectively.
Figure 2: [5]
While there is a general upward trend, in the developed world, there are concious efforts being implemented
to address energy consumption, in order to reduce emission and carbon footprint, while on the other side of
the spectrum, similar tactics are occasionally discussed but are generally not taken as seriously.
2

3. 2.2 Transportation
High speed transportation has led to easier, faster and more frequent international travel. A direct result of
this has been a staggering rise in energy consumption as a direct result of travel. In the Europe, air travel is
second largest energy consumer in transportation, after road. In 2013, over 840 million passenger flew through
European airport, with 72.3 million of them flying through London’s Heathrow airport; compared with only
803 million in 2008. Economic crisis in 2009 led to a 6% fall in flights[6], and thus a slight fall in air travel
energy consumption, and overall transport energy consumption. Passenger numbers are expected to rise in the
future, and so newer aircrafts are being designed with increased fuel efficiency.
Road transportation has been the main source of energy consumption in Europe, and globally for over 50
years[7]; a trend that is expected to continue in the future[15]. Figures 3a and b (shows intensity) show energy
consumed by the four major means of transportation (road, air, water and rail) between 1970 and 2013. The
graph shows steady increase in all sectors until around 2008, where economic crisis and record high oil prices
caused a fall in transportation, especially in air.
(a) (b)
Figure 3: [7]
2.3 Domestic Consumption
Domestic consumption, which involves electricity, natural gas, petroleum, small amounts of bioenergy and
solid fuels, has decreased by 7% in the UK since 2000[8] although number of households and total population
have risen by 11 and 7 percent respectively. The reduction in domestic consumption can be attributed to
increased home efficiency, more UK home are better insulated and thus loose less energy when heated; and
appliance efficiency, improvements in technologies mean home appliances, like TVs, fridges etc., use less energy
than their predecessors; and new smart appliances have energy saving modes designed to reduced energy
consumption, especially in standby mode.
2.4 Industry
In 2011, the US industrial sector (including construction, manufacturing, agriculture etc.) consumed 1,033
trillion Btu (British thermal units) of energy[10], compared to 1,675 trillion Btu in 2002 and 1,168 trillion Btu
in 1989; figure 4a below shows energy consumption trend, for the US industrial sector, between 1989 and 2011.
Similarly, in 2013, UK industries consumed 24.2 million tonnes of oil equivalent (mtoe), a 61% decrease from
1970 (1Btu = 2.5219021687207×10−14Mtoe). Figure 4b shows UK industry energy consumption between 1970
and 2013.
(a) [10] (b) [11]
Figure 4
3

4. These reductions are as a result of improved efficiency in energy generation, and conversion from one form
of energy to another. High oil prices, in the 1970s, played a role in not only reducing energy consumption
(see figure 5 below), but in shifting preferred energy source from petroleum and solid fuels to gas. By 2013,
dependence on petroleum had fallen from over 50%, in 1970, to less than 25%, making electricity and gas
(natural gas) the preferred energy sources.
Figure 5: [11]
3 RENEWABLE ENERGIES
In recent years, the global trend has been a steady move towards renewable energy sources. In 2012, 19% of
global energy was produced from renewable sources, with 10% from modern renewable sources like wind, solar
and hydro, and 9% from traditional biomass[13], like fire wood. Renewable sources are estimated to account
for 22.1% of total global energy in 2013[13], the actual figure will be confirmed in REN21’s 2015 renewables
report.
3.1 Hydro
In 2012, hydropower was the second most preferred modern renewable source, at 3.8%[13], but by 2013, this
is estimated to have grown to 16.4%[13], of total global energy generated, to become the most preferred source
of renewable energy. REN21 estimates global hydropower capacity reached 1,000 Gigawatt (GW) by 2013, a
4.16% rise from 2012, and 39.8% since 2004. China is the world’s largest hydropower producer, producing over
700 TWh in 2010.
Hydropower utilises the power of running water to generate energy. Most hydropower is produced from
dams but, wave, which capture energy from ocean surface waves and tidal power, which utilize tidal energies
are promising future forms of hydropower but are currently not mainstream.
3.2 Wind
Between 2004 and 2013, wind power capacity is estimated to have grown by over 500% (from 48GW to
318GW[13]). While, still less than hydropower, wind power is one of the heaviest invested technology globally
by public markets, governments and private investors; and investment in wind is predicted to keep growing in
coming years due to the relatively low associated costs and numerous cases where wind can already be seen to
be financially lucrative[19].
(a) Public Markets (b) Venture Capitalist/Private Equity
Figure 6: 2013 investments in Renewable Energy ($B)[14]
4

5. 3.3 Solar
According to a 2014 article in the guardian[18], solar panels are now less than a quarter of their 2008 prices.
This, together with evidence of success in South Africa and Germany, has made solar energy more attractive
to government and private investors. By 2020, Bloomberg estimates a 300% increase in solar power capacity,
from the current 150GW, and over by 1100% by 2030. Over 80% of global solar energy comes from China, the
EU (especially Spain) is the second largest producer, at 9.5%. China’s position is due to heavy government
investments in renewable energy, especially solar and hydro power, in recent years. Since 2008, China has
been the largest manufacturer of solar panels (with over 400 companies[20]), and by 2010 accounted for a huge
majority of global photovoltaics production annually[20].
3.4 Bioenergy
Biofuels are the oldest form of renewable energy. They are derived from biomass, biological matter from
living organisms, and are used to generate energy in much the same way as fossil fuels, which makes the move
from fossil fuel cheaper, as fossil fuel energy generators (e.g. gas turbines) can easily be converted to biofuel.
Bio-power generation increased from 227 TWh, in 2004, to 405 TWh in 2013[13], and there is a global trend
in transportation and other sectors, where biofuel is used as a welcome alternative to conventional fuels, figure
7 a and b show trends in the biofuel industry.
(a) Ethanol, Biodiesel, and HVO Global Produc-
tion
(b) Wood Pellet Global Production
Figure 7: [13]
Although there is growing interest in renewables, sluggish government movement on creating long term
policies has hindered investment in renewables; and while regulators are catching up to the task ahead, there
is still a lot of work to do. Also, the slow adaptation of renewable energy by most international government,
has meant that most strides in renewables, has been made by the private sector.
There is evidence that developing countries could lead innovation in renewable energy. China has, since 2010,
been leading the way in hydro, solar and wind power, with India, Brazil, Turkey and Kenya investing more
annually (2013 data)[13], than most of Europe (excluding Germany and Spain), and the rest of the developed
world (excluding the US). Figure 8a, below shows predicted energy demand growth by region, and figure 8b
shows a foretasted energy situation for 2035.
(a) Energy Demand by Region (b) New Energy Forms
Figure 8: [15]
5

6. 4 ENERGY PRODUCERS & CONSUMERS
4.1 Current
The number one source of energy globally, is and has been oil since 1965 (see figure 9a). Although oil
accounts for most energy produced globally, a significant amount of global electricity comes from coal. China
accounts for an large proportion of global coal consumption (see figure 9b). This demand has been growing
steadily since 1965 due to rapid industrialisation.
(a) Energy Consumption by Fuel
(b) Coal Consumption by Country
Figure 9: [15]
4.2 Future
By the second decade of this century, North America is expected to be energy self sufficient, and by the
end of 2035, the US is expected to be the second largest exporter of natural gas. This means all primary
energy imports (oil, gas etc.) would be concentrated in Asia and Europe[15]. The general picture is a shift
not only from where energy is produced, but from what sources is energy produced. Trends paint a loosing
picture for oil as more environmentally friendly alternative become more mainstream. Natural gas, however,
is expected to grow in popularity across the spectrum starting with the power industry, through industry and
finally transport.
Figure 10: [15]
As stated above, demand for coal in China has been growing over the past few years with China’s mass
industrialization, but as the economy stabilizes, there will be a gradual shift from coal to natural gas, as the
preferred source of energy, and by 2035, there is expected to be a declining trend in coal demand in China[15].
The same picture, although at a later time, can be seen in developing and emerging economies such as India.
These economies are still in the process of industrializing and so need cheap energy, i.e. coal, to ensure they
do not hinder economic growth.
5 ENVIRONMENTAL IMPLICATIONS
Increasing carbon emissions are a result of increasing demand for energy. Because, the largest and third
largest sources of global energy are oil and coal, it is expected that emission would be increasing. However, the
6

7. shift towards natural gas brings promise of a possible falling emission trend simply because burning natural
gas produces a fraction of CO2 emissions of coal or oil. Also, the fuel mix plays an important role in emissions.
Energy, and in particular electricity, is generated from a whole host of sources, from nuclear power to wind
and coal. Each source has it associated carbon and financial cost. Currently, the energy fuel mix in Europe,
includes oil, nuclear, natural gas, renewables and coal (see figure 11). Policies and targets across the EU
and most of the world (including developing countries) have been set to reduce oil and coal use and increase
renewable and other more eco-friendly sources.
Figure 11: [16]
UK
The UK was the first country to set legally binding CO2 emission targets. These targets set out to achieve
emissions which are 80% less than 1990 figures, by 2050. These targets would be achieved by first, reducing
energy demand by educating and helping private and public sectors use electricity more efficiently. Between
2008 and 2011 the government spent 3.5 billion to help increase home energy efficiency. Two, investing in low
carbon energy generation. By 2011[17], the UK had invested over $9 billion in clean energy (see figure 12).
And finally, reporting on progress every few years.
Figure 12: [17]
Europe
In 2012, 10% of global emissions came from the EU, however, Europe’s share of global CO2 emission have
been falling since the adoption of better environmental policies. The most recent review into Europe’s 2020
emission target shows Europe is still on track. In 2002, EU member states, together with non EU members,
set out percentage reduction targets over a base year in the Kyoto treaty. The first phase of the treaty required
an 8% reduction in emission between 2008 and 2012, all EU members achieved their targets and, cumulatively,
achieved 11.8% reduction[18].
Rest of the World
It has become clear to the rest of the world that global warming and carbon emissions are everyone’s
problem. Scepticism, mostly in the developing world, has evolved into belief, and as such we are seeing more
international participation in the fight against climate change. Figure 13 below compares the number of
countries with renewable energy policies in 2005 (13a) to 2014 (13b). By 2014, over 100 more countries joined
the initial few and now have defined renewable energy targets.
7

8. (a)
(b)
Figure 13: [13]
6 AUTOMOTIVE INDUSTRY
In an attempt to tackle global warming, numerous restrictions, requirements and guidelines have been
imposed on the automotive industry over the past few years. A lot of these restrictions target emissions and
heavily penalise low performing vehicles. As a result, the trend, in automotive, has been a gradual move
away from fossil fuels, to alternative, more eco-friendly fuels, such as bio-fuel, liquefied petroleum gas (LPG),
hydrogen and electricity.
Biofuels make up a huge percentage of alternative technologies employed by automotive manufacturers to
meet emission quotas. The most commonly used biofuel for vehicle use is an ethanol-fuel blend consisting of
85% denatured ethanol fuel (consist of atleast 5% of highly flammable methanol) and 15% gasoline known as
E85. The chart below shows biofuel use since 1995, and the breakdown by fuel.
Figure 14: [11]
Between 1995 and 2010 majority of growth in the use of alternative fuels has been in E85. This is largely
due to how relatively easy the conversion from gasoline to E85 and the relatively high return on investment in
the E85 production.
There are two main ways of implementing electricity in vehicles; hybrid and full electric
1. Hybrid vehicles combine two or more systems, usually an internal combustion engine and an electric
motor, to produce required power. The advantages for hybrid systems include:
(a) Lower Emissions The total work is split between the technologies making the emission from the
internal combustion part of the system less, as lees fuel is burned to produce the same power.
(b) Smaller Engines Hybrid systems tend to be smaller than regular engines. This means the system
is lighter and thus needs less power to do the same work, and, as a result, less fuel.
However, disadvantages of hybrids include:
(a) Lower Power Output Hybrids are usually designed for fuel economy, not power and thus they
tend to produce less power than their full fuel counter parts.
(b) High Maintenance Costs The complexity of hybrids mean they cost more to maintain.
2. Fully Electric cars are powered exclusively by electric motors. They usually have batteries, where
electricity is stored, or collect electricity from an external source. Advantages of these engines include:
8

9. (a) No Emission Because fully electric engines do not burn anything, there are no emission, and
regulation to worry about.
(b) Low Operating Costs Electricity is reasonably cheap in most parts of the world, and, as a result,
it is cheaper to run electric engines; and, in a situation where there is access to renewable energy,
e.g. wind, solar, there could be no operating costs.
There are some disadvantage to this technology, a few include:
(a) Long recharging times Battery operated electric engines take much longer, anywhere from 20
minutes to a few hours, to recharge, than standard engines, which can be refilled in a few minutes.
Also, because recharging requires special equipment, getting stranded is a bit more likely.
(b) Limited Range Range refers to how long (or far) the engine can run before depleting all its charge.
This, coupled with the long recharging time, means continuous work is a bit more stressful. Also,
electric engines usually drain faster than they recharge, so keeping it plugged in would not be enough
to keep it running indefinitely.
By 2035, a decrease in demand for transport fuel is predicted, mainly because of efficiency improvements, that
said, most transport fuels is expected to remain oil (about 80%[15]), because these significant improvements, in
fuel efficiencies by automotive manufacturers, are best achieved by hybrid vehicles. It is also expected that, by
2035, natural gas will overtake biofuels as the preferred alternative fuel due to the rate of adoption of natural
gas in the automotive industry.
(a) Transport Demand by Fuel (b) Five Year Increments by Fuel
Figure 15: [15]
7 Developing World
Contrary to popular belief, the developing world is making strides in renewable energies. Investment in
renewable sources in developing economies are catching up to developed economies, and have overtaken the
developed world in wind power (see figure 16). This is largely because of the abundance of natural energies
either in form of sun light, for solar power, water for hydro or even geothermal power. For example, some
isolated communities in Africa use wind turbines to generate electricity because of a lack of affordable means
to transport energy generated in power plants. Kenya, has the highest number of solar panels installed per
capita.
Access to energy, and renewable energy in this case, has proven to be an adequate means of alleviating poverty.
Access to energy means access to more mechanised labour, which is the stepping stone to industrialisation.
It also, helps improve the standard of living of the local people. There is not need to travel long distances
to fetch wood for cooking or warmth; chances of water borne diseases are reduced as electricity based water
purification systems can be installed; and a reduction in cancers caused by continuously inhaling burnt wood
or plant matter, and a reduced risk of carbon mono-oxide poising.
However, the developed world was able to achieve levels of economic growth due to cheap energy during
industrialisation, China and India are examples of countries where rapid industrialisation meant less emphasis
could be placed on renewable energy, and while India and China are leading the way in most renewable technol-
ogy, it is possible to say that if they had focused on renewable technology, at the start of their industrialisation,
they would not have achieved the level of economic growth as quickly as they did.
9

10. Figure 16: [17]
Finally, energy consumption in the developing world is lower than in the rest of the world, but historical
evidence shows that as economies grow, so does their demand for energy; these developing economies are
growing at impressive rates and this will no doubt effect the environment, but how much and effect they have
will depend on available fuel mix, more renewable and little to not fossil fuels would be referable, and global
energy restrictions and laws. With regards to the international community helping foster eco-friendly energy
generation in the developing world, I think it is important for there to be intrusive measure put in place,
like a global fund to encourage renewable energy generation in developing countries, to help ease the cost
of renewables. Or educational support to show there are ways of generating energy other than coal, oil and
traditional biomass.
References
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