Tag: Primary energy

Over 50% of the daily calories for an average person should come from carbohydrates, the body's primary fuel. The simple question, **what is your first source of energy?**, has a multifaceted answer depending on whether you're talking about human biology or human history.

Globally, non-renewable energy sources still supply the majority of the energy we use. Our everyday reliance on electricity, a secondary energy source, is fundamentally dependent on these and other primary sources, which are converted to deliver power seamlessly to homes and industries.

According to the U.S. Energy Information Administration, electricity is a secondary energy source, and it is undoubtedly the most widely used in the modern world. Unlike primary sources found directly in nature, such as coal or wind, secondary sources are manufactured from these original inputs. This transformation makes electricity incredibly versatile, powering everything from our homes to industrial machines and global communication systems.

According to the Sustainable Energy Authority of Ireland (SEAI), the sum of all primary energy inputs into a national energy system is called the Total Primary Energy Requirement (TPER). This metric is essential for governments, energy analysts, and policymakers to understand a country's total energy demand and how different sources contribute to it.

For the first time in history, renewables surpassed coal as the leading source of global electricity generation in the first half of 2025, but the answer to what is the biggest source of energy depends on how you measure it.

Globally, approximately 80% of the primary energy consumed still originates from fossil fuels, despite rapid growth in renewables. Understanding **where does most of our energy come from** requires distinguishing between primary energy and electricity generation sources.