Prueba de correlación de la hipótesis específica 3

As projected by WITCH, Figure 5.16 depicts the generation pathway globally under the different pollution abatement targets and scenarios, with percentages presented in The BaU case expects electricity generated via the cleaner fuels (nuclear, hydro and renewables) to increase from 33% in 2010, to 36% by 2035 as projected by WITCH.

In 2050, fossil fuel generated electricity is 37%. For the abatement cases of 450ppm, 600ppm and 750ppm, the cleaner technologies (nuclear, hydro and renewables) play a much larger role in the energy mix. For the 750ppm case, the cleaner generation technologies rise from 33% in 2010 to 43% in 2035 and 49% in 2050. For the

World Electricity Generation Capacity Mix (Gw )

2010 2015 2020 2025 2030 2035 2040 2045 2050

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World Electricity Generation Capacity Mix (Gw ) under 750

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Renewables

World Electricity Generation Capacity Mix (Gw ) under 600

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Figure 5.16: Global Electricity Generation Capacity Mix (WITCH model output)

600ppm case, cleaner technology based generation rises to 58% by 2035 and 67% by 2050. In the most extreme case of 450ppm, cleaner technology based generation increases to 75% by 2035 and 91% by 2050.

In 2010, the global generation mix is dominated by fossil fuels with 32% coal, 25%

for natural gas and 9% of oil. Low carbon generation technologies include 5%

renewables (excluding hydro), 8% for nuclear and 20% for hydro. This can be ovserved in Table 5.3.

Table 5.3: Global Electricity Generation Capacity Mix (WITCH model output)

BaU 2010 2015 2020 2025 2030 2035 2040 2045 2050

Renewables Globally

Renewables excluding hydropower (i.e. wind and solar power) grow significantly across all four cases under WITCH. In BaU, it rises from 5% in 2010, to 14% in 2035 and 17% in 2050. For 750ppm, renewables rise to 19% by 2035 and 24% by 2050.

The 600ppm case sees this mix increase to 27% by 2035 and to 37% by 2050. For the 450ppm case, 2035 will expect a 37% mix with 2050 expecting 55%. Hence, wind and solar is projected to be the fastest growing electricity generation technology, both worldwide and at regional level.

WITCH believes that electricity from wind and solar is generated using only setup and maintenance costs. The rapid development of wind and solar power technologies in recent years has led to a reduction in investment costs; beneficial effects from learning-by-doing are expected to decrease investment costs even further in the next few years. If the same model is run with 2015 as the base year, instead of 2010, this will become more apparent, as cost reductions and falling costs attributed to technology know-how and best practices will be reflected in this generation method.

Nuclear Globally

For BaU nuclear starts at 8% in 2010 and remains around the 9% mark until 2050 for WITCH. For the 750ppm case, nuclear power rises to 9% in 2035 and 12% in 2050.

In the more stringent pollution abatement cases of 600ppm, nuclear rises to 13% in 2035 and 16% in 2050. For 450ppm, nuclear rises to 17% in 2035 and 21% in 2050.

Since nuclear power is a capital-intensive technology, fast-growing regions, such as China and SASIA see an increase, whilst a decline in mature economies is observed.

This characteristic and the fact that nuclear energy does not emit CO2, make nuclear power an interesting option for the future. However, countries are hesitant to implement such a technology due to controversial difficulties such as the long-term disposal of waste and proliferation risks. Light Water Reactors (LWR) are the most reliable and relatively least expensive solution today, but a major expansion might revive the Fast Breeding Reactors (FBR). They re-process the spent fuel to feed the nuclear reactor again, and thus produce less waste and result in less waste storage concerns.

Hydropower Globally

Hydropower equates to 20% of electricity generation capacity in 2010, before falling to 11 to 16% by 2050 for BaU and 450ppm respectively as per WITCH. In the BaU case, hydropower falls to 11% of electricity generation capacity, whereas for 750ppm this number is 13%, 600ppm 15% and 450ppm 16%.

The reason for gradually switching away from hydropower and favouring renewable energy in all cases can be attributed to difficulties in locating suitable plant locations for additional new-build capacity. Hydropower plants not only require suitable bodies of water to store gravitational energy, but also often require the displacement of local communities or the flooding of fertile farm land. Wind turbines and solar farms, in contrast, are less restricted in plant location selection, as they can be located in remote and often arid sites.

Coal Globally

Coal remains the largest provider of electricity globally, remaining around the mid 30% in the BaU case. In BaU, from 32% in 2010, it rises to 36% in 2035 and 40% in 2050 under WITCH. Substantial deployment of coal is expected in Asian countries such as India and China. In the 750ppm case, coal steadily falls to 29% in 2035 and 23% in 2050. This shift away from coal is even more evident in the more stringent abatement cases. For 600ppm, coal declines to 13% in 2035 and in 2050 it makes up 6% of generation. For the 450ppm case, it declines to 7% by 2035 and 2% by 2050.

Coal generation is, along with gas, the least expensive electricity generation technology in all countries. It is cheaper than gas in all regions rich in coal reserves, such as KOSAU, CHINA, NEWEURO, and SASIA, and it is equivalent to gas in the USA and more expensive than in the others. The analysis does not take into account the benefits of IGCC with CCS as steps towards emission reduction.

Natural Gas Globally

Electricity generated from natural gas starts off at 25% in 2010 and falls to 23% in 2035 in the BaU, falling to 19% in 2050. Under WITCH, the 750ppm scenario expects gas to account for 23% in 2035 and 22% in 2050. For 600ppm, gas falls to 23% in 2035 and 20% in 2050. For 450ppm, gas decreases to 13% in 2035 and to 5%

in 2050.

The reason for the fall in gas consumption in the 450ppm case is that under pressure to reduce emissions, natural gas becomes expensive given its exhaustibility. Since gas-based electricity generation is a fuel-intensive technology and once gas prices increase the environmental concerns displaces gas for other generation technologies.