A Brief Discussion on the Current State and Future of Energy Utilization

A Brief Discussion on the Current State and Future of Energy Utilization

The cleanliness of energy needs to be understood from two perspectives: the intrinsic characteristics of the energy source itself, and the processes and technologies by which we use it under current technical conditions.

In essence, all forms of energy used by humanity, except nuclear energy, come from different forms of stored solar energy. Fossil fuels (coal, oil, and natural gas) and bioenergy (combustion, fermentation, etc.) originate from photosynthesis driven by sunlight. Tidal energy, hydropower, and wind energy arise from the thermal effects of solar energy, while solar power itself (photovoltaic generation and solar heating) comes directly from its photoelectric and thermal effects. On the timescale of human activity, fossil fuels and nuclear energy are regarded as non-renewable resources, since their formation cycles span hundreds of millions or even billions of years—far beyond the scale of human energy use. By contrast, wind, hydropower (including tidal power), solar energy (photovoltaic and solar thermal), and bioenergy are renewable. From the perspective of sustainable human development, unless there is a major breakthrough in fundamental science in the near future, renewable energy is the ultimate option that can sustain the continuation of human civilization, while non-renewable energy can only serve as a transitional solution. Yet the contradiction between humanity’s current dependence on fossil fuels and nuclear power, growing energy scarcity, and the inadequacy of renewable energy technologies should be taken seriously and approached with vigilance.

Then there is the issue of pollution. Under current technological conditions, humanity still relies primarily on combustion to use fossil fuels. Excessive burning increases the proportion of carbon dioxide in the atmosphere, intensifies the greenhouse effect, and drives the continued rise in global temperatures—developments that may bring devastating consequences for all humankind. At this level, all uses of fossil fuels constitute environmental pollution. Even so, compared with the severe pollution caused by the nitrogen and sulfur compounds released from burning coal and oil, natural gas, which mainly produces carbon dioxide, may be regarded as relatively low-polluting. In the short term, cleaner coal technologies and natural gas—energy-use patterns whose emissions are dominated by carbon dioxide—represent the minimum acceptable baseline for humanity’s energy use.

Wind, hydropower, and solar energy do not inherently create additional pollution in their energy form and therefore belong to the category of clean energy (geothermal energy also falls into this category). However, wind power is constrained by reliability because of its intermittency and instability, and at present it cannot serve as a primary energy source. The total exploitable amount of wind and hydropower is also limited by technical capability and natural conditions, and cannot fully meet current and future energy demand. Solar photovoltaics cause substantial pollution during manufacturing—mainly in the purification of silicon materials—and their efficiency still needs further improvement. The long-term environmental impacts of constructing large hydropower stations also require further observation and research. Nevertheless, although wind, water, and solar energy still have many shortcomings today, they remain humanity’s best option for the future—and perhaps the only one. Overall, their use is low-pollution and sustainable.

Finally, nuclear energy is a Pandora’s box among energy sources. In formal terms, because of the nature of its raw materials, nuclear fission, like fossil fuels, can only be a transitional solution rather than the ultimate answer to energy. Controlled nuclear fusion, meanwhile, is a fierce beast that has not yet been tamed; whether it can be mastered, and when, remains uncertain. Humanity’s future and hopes certainly cannot rest entirely on it.

So, before energy technology makes major advances capable of supporting sustainable human development, are we doomed to sit still and wait for the worst while continuing down the current path? Of course not. Since the Industrial Revolution, humanity has used energy under the assumption that it is inexhaustible, in a rough, extensive, and disorderly manner. This has made energy waste—and the additional pollution that comes with it—especially severe. Improving this situation could, to a considerable extent, ease the energy crisis until technological innovation or scientific breakthroughs arrive. In terms of improving the comprehensive use of energy, one effective path is to apply advanced computer technologies and use big data, the Internet of Things, and machine learning to coordinate existing clean energy sources, while also making integrated use of energy in the forms of electricity, cooling, and heating. By doing so, we can improve energy efficiency and reduce waste. This is the so-called “smart energy” solution—a practical path, and also a responsibility we must shoulder today.