Energy Sources, Environmental Challenges, and Sustainable Solutions

Posted on Nov 25, 2024 in Geology

The Energy Problem

When muscular power was not enough, the wheel and the steam engine, fed with firewood or charcoal, emerged. Humans began to consume the energy they had spent hundreds of millions of years accumulating. Fossil fuels are plant or animal remains buried.

Each year we spend what took a million years to form. Experts estimate oil production will peak between 2020 and 2040. Afterward, oil may only be available to richer countries.

Hydropower

River water can be dammed, leading to a turbine that generates electricity. Reservoirs store water for irrigation and consumption, also preventing floods. However, this can inundate large areas, destabilize deltas, and disrupt aquatic life. Consequently, many dams are being dismantled.

Nuclear Energy

Worldwide, 435 nuclear power plants (9 in Spain) provide 17% of electricity. There are also about 50 nuclear submarines. In nuclear reactors, uranium enriched with plutonium-235 is bombarded with neutrons, causing fission and releasing energy. The heat vaporizes water, driving a turbine to generate electricity. Used nuclear fuel is dangerously radioactive for thousands of years, and a safe disposal method remains elusive.

Wind Energy

This energy source has increased tenfold in the last decade, especially in Europe. Offshore wind farms are the future due to more constant winds, but the impact on bird migration routes needs study.

Solar Energy

Solar energy is inexhaustible and can be converted directly to electricity via solar panels or to heat in solar thermal plants. In the latter, water boils, steam drives a turbine, generating electricity. It’s ideal for tropical countries with intense, constant solar radiation.

Energy Obtained by Biofuels

Many cars run on gasoline mixed with alcohol (ethanol), produced by fermenting corn or sugar cane. Biodiesel, made from oilseeds, can replace diesel. However, biofuel production also consumes oil and requires large farming areas.

Energy from Hydrogen

Hydrogen is a potential future fuel. Its combustion produces only water vapor. Hydrogen can be obtained:

  • With photovoltaic panels: These use solar energy to decompose water into hydrogen and oxygen.
  • From natural gas (methane, butane, etc.): This method requires high temperatures, often obtained by burning gasoline.

Nuclear Fusion Energy

Nuclear fusion, like in stars, releases vast energy. Scientists have achieved this in the laboratory. Its advantage is that it doesn’t pollute or generate radioactive waste. Geothermal and tidal power are other alternatives.

Overpopulation and consumption create imbalances called impacts.

INCREASING CO2

Atmospheric CO2 concentration was constant (280 ppm) for a thousand years, but since 1800, it has rapidly climbed to 369 ppm.

GLOBAL CLIMATE CHANGE

  1. In the twentieth century, average atmospheric and ocean temperatures increased by about 0.7°C.
  2. Arctic snow and ice volume decreased by 22% since 1970.
  3. Sea levels rose 10-25 cm in the last century.
  4. Hurricane frequency increased due to warmer equatorial waters.
  5. The speed of the global conveyor current decreased, affecting CO2 transport.

What to do?

  • In energy: Replace coal-fired power plants with less polluting alternatives, invest in renewable energy, explore CO2 capture, and build more nuclear power plants.
  • In transport: Encourage public transport, cleaner diesel engines, or hybrid vehicles.
  • In homes: Improve building orientation, insulation, and heating/cooling systems.
  • In industry: Recycle, use cleaner technologies for steel, cement, and paper production.
  • In agriculture: Improve livestock management to reduce methane emissions.
  • In forestry: Shift from deforestation to reforestation.

A slowdown in global ocean currents, which transport CO2 to the deep sea, could lead to unstoppable atmospheric CO2 accumulation.

ACID RAIN

Burning biomass and fossil fuels generates NO2 and SO2, in addition to CO2. Fertilizers also release NO2. These gases combine with water to form carbonic acid (H2CO3), nitric acid (HNO3), and sulfuric acid (H2SO4), resulting in acid rain, which damages vegetation, wildlife, and lakes.

Biofouling

Living organisms are exposed to harmful substances (detergents, medicines, insecticides, etc.) that dissolve in water and enter our bloodstream. The pollution levels in the Eskimo population exemplify this global problem.

Minamata Disease

Consuming contaminated products, even with low pollution levels, leads to bioaccumulation and irreversible damage. The concentration of these substances increases through the food chain (biomagnification).

SOLID WASTE

Solid waste is a significant and unmanageable problem. Each Spaniard generates 1.2 kg of waste per day. While a local pollutant, its management is a global issue. Controlled landfills minimize visual impact, but increasing waste volumes necessitate incinerators, which emit greenhouse gases and harmful particles. Proper filters can mitigate this.

PLANS FOR SURVIVAL

The term “sustainable development” was coined in 1987 by a UN commission. It refers to development that meets present needs without compromising future generations’ ability to meet their own. Key principles include:

  • Not exploiting renewable resources faster than their replacement rate or without using alternative resources.
  • Not emitting waste beyond the environment’s absorption capacity.

ITEMS FOR SUSTAINABLE DEVELOPMENT:

  1. Almost unanimous support from global politicians.
  2. Sustainable development would allocate significant resources to the third world.
  3. Strong support within the scientific community.

POINTS AGAINST SUSTAINABLE DEVELOPMENT:

  1. Politicians may not be the best people to achieve balance with global companies.
  2. Real sustainable development might imply de-industrializing more advanced countries.
  3. Notable exceptions exist, such as James Lovelock, promoter of the Gaia theory.