Can renewable energy sources contribute to reducing global warming?

As a large percentage of the CO2 emitted by us is owing to the use of fossil fuels for energy. Renewable energy, with its much lower carbon footprint, is one of the most effective tools we have in the fight against climate change.

The carbon footprint of power generated from renewable energy sources is significantly lower than that for fossil fuel based energy sources, sometimes as low as 5% of the former (Source). As a result, it is obvious that if a large part of our power generation and heating requirements come from renewable energy sources, we could be emitting far less CO2 for the same amount of energy utilized!

Wind and solar energy have seen remarkable growth and significant cost decreases over the past decade. As a result, the overall economics of renewable energy is becoming increasingly competitive with fossil fuels all around the world. In some places, investing in new renewable energy power plants is already cheaper than continuing to operate old, inefficient and dirty fossil fuel-fired or nuclear power plants.

Along with hydropower, renewable energy sources today already contribute about 2 TW of total electricity capacity worldwide of a total of about 6.4 TW, almost 30%. As the share of renewables in electricity installed capacity and generation increases, so will its contribution to the reduction of CO2 emissions.

While scaling renewable energy sources in order they contribute a majority of our electricity and heat sounds like a great idea, there are significant challenges to large-scale replacement of fossil fuels with renewable energy sources. For one, most renewable energy sources are intermittent (sun shines only during the day!), and thus energy storage becomes important. There are other operational constrains as well that act as the roadblock to large scale renewable energy adoption.

All the same, estimates indicate that by 2050, solar energy would have likely replaced coal as the largest source of power generation. If this and similar trends happen for renewable energy sources, we are talking about renewable energy starting to make considerable a considerable contribution to global warming reduction.