Questão de Inglês — conectivos e referência pronominal

Renewable energy is no longer a niche industry. Over the last decade, the cost of electricity generated by solar panels and wind turbines has fallen so sharply that, in many countries, building a new solar farm is now cheaper than building a new coal or gas power plant. As a result, investment in clean energy has surpassed investment in fossil fuels for the first time in several major economies.

Despite this progress, the transition is far from complete. Fossil fuels still account for the largest share of global energy consumption, and demand for electricity keeps growing, driven by population growth, urbanisation and the spread of air conditioning. One of the main obstacles is intermittency: the sun does not always shine and the wind does not always blow. Without efficient ways of storing energy, power grids must rely on conventional plants to meet demand at night or on calm days.

Battery technology has improved considerably, but large-scale storage remains expensive. Engineers are also exploring alternatives such as pumped hydroelectric storage, in which water is pumped uphill when electricity is abundant and released to drive turbines when it is scarce.

The expansion of renewables also raises social and environmental questions. Large wind and solar projects require vast areas of land, and in some regions local communities have complained that they were not consulted before construction began. In addition, the minerals used in batteries and panels, such as lithium and cobalt, are often extracted under poor working conditions.

Analysts agree that the shift to clean energy is irreversible. The pace of that shift, however, will depend largely on political decisions, grid modernisation and the ability to address the concerns of the people most affected by it.