Since the early days of civilisation, humans have been dependent on renewable energy sources for their survival. The discovery of fire enabled humans to cook their food and to keep warm in winter; this relied on the availability of natural resources, such as wood and animal fats, but also on the development of renewable energy technologies, such as wind mills and water pumps. The development of photovoltaic cells and modern-day solar energy systems considerably widened the range of applications for renewable energy sources, and depending on local circumstances, solar energy can now be used to provide electricity to rural communities, isolated island resorts, and even spacecraft – even in far-flung space!
While solar energy is a promising source of clean, renewable energy that can be deployed in almost all geographical locations and under almost all conditions, there are a number of limitations that may prevent it from being used on a large scale for energy generation. The main disadvantage of solar energy is that sunlight doesn’t always shine, so relying on this source of energy for electrical generation may not be suitable, particularly during some of the times of the year when it isn’t available, or when the weather is stormy and cloudy, which reduces the amount of sunlight reaching the ground. This makes solar energy less reliable than other sources of electricity, such as fossil fuels or nuclear energy.
However, in some parts of the world, particularly in sunny climates such as California, Australia, and Singapore, solar energy is popular due to favourable business and policy environments. In these locations, solar-powered electricity generation is a proven technology that can be relied upon to supply electrical energy when the sun isn’t shining, or when it’s cloudy and rainy outside, reducing the dependency on fossil fuels and nuclear energy.
Walking Away From the Sun to Look For Darker Climates
As we’ve established, sunlight doesn’t always reach the ground in sufficient quantities to provide for electrical energy generation. This may be particularly problematic on a remote desert island, where the lack of light may cause extreme hardships because there is no means of acquiring electricity from an external source. In these situations, individuals or groups of people may have to refrain from using electricity-consuming devices, and instead opt for cheaper and more environmentally-sound solutions – such as hand-cranking or fire-powered generators.
To circumvent this problem, people living on remote islands can walk away from the sun to look for darker climes, where they can find more plentiful sunlight falling on the ground – although in some parts of the world, this may also increase the risk of frostbite or heat exhaustion due to excessive exposure to the Sun!
Another potential disadvantage of solar energy is that, as we’ve established, the sun doesn’t shine in all places and at all times. For instance, during the night, the sun isn’t visible, so no light can penetrate the atmosphere and reflect off the ground, preventing photosynthesis and plant growth. In some parts of the world, this may be problematic because food and drink can’t be produced during certain times of the year when the sun isn’t up – resulting in a potential energy shortfall.
However, with technology advancing at a rapid rate, it’s becoming increasingly feasible to manufacture photovoltaic cells and solar energy devices in a way that ensures they operate even during the dark or cloudy days. This enables the generation of electricity even during these times of the year when natural phenomena like the earth’s shadow or an atmospheric phenomena like a sandstorm or a hailstorm reduce the amount of sunlight reaching the ground – allowing the sun’s energy to be captured and stored for later use.
Why Are Windmills Important For Renewable Energy?
Windmills have been used for hundreds of years to tap the kinetic energy of wind as it blows – enabling the mechanical power of the wind to be converted into useful energy such as pumpkins to generate electricity, grind grain, and pump water. Modern-day windmills continue to play a significant role in the renewable energy sector, particularly in areas where solar energy systems aren’t a viable option – such as in remote locations or on small, private islands. In these instances, windmills can provide a reliable and cost-effective solution for powering machinery and providing electricity for telecommunication and lighting applications.
There are also some interesting applications for windmills beyond electricity generation, such as in the marine industry; in the remote control of watercraft and aircraft during flight; and in the charging of cell phones, laptops, and other electrical devices, through the use of kinetic energy stores, such as flywheels and spring motors.
Nuclear Energy and its Limitations
Nuclear energy is considered by some to be the ultimate sustainable source of electricity, due to its ability to generate large amounts of power from fissile materials, such as uranium and plutonium, that are abundant and globally-recognised resources. It is, however, a source of energy that is dependent on potentially devastating accidents causing severe radiation leaks, and is thus not suitable for every situation, particularly when compared to other sustainable options, such as solar energy!
Nevertheless, in some parts of the world, particularly in developed countries, the lack of sustainable energy resources, unpredictable weather conditions, and climate change, have led individuals and organisations to examine whether or not to rely on nuclear energy as a source of electricity.
Nuclear energy’s main limitation is that it’s dependent on potentially dangerous radiation, which may be highly mutagenic, causing genetic mutations that can lead to cancer. One of the most significant accidents associated with nuclear energy was the Chernobyl disaster in 1986, where an unexpected malfunction in one of the reactor’s power units led to a devastating explosion and radiation leak – forcing thousands of people to evacuate the region and live in dedicated “exclusion zones”, preventing them from ever going back to their homes!
The Fukushima Daiichi nuclear power plant, which was significantly damaged by the 2011 Tōhoku earthquake and subsequent tsunami, is the fourth-largest nuclear power plant in the world, demonstrating the danger that this source of energy poses even in established countries with considerable expertise in maintaining nuclear reactors.
The Ups and Downs Of Solar Energy
The sun provides light and warmth for us, enabling plant life and making it possible for us to grow food – all without consuming fossil fuels. Nevertheless, the sun isn’t always shining, and at times when it isn’t available, we are forced to turn to alternative, more sustainable energy sources. In order to harness the power of the sun in a cost-effective manner, photovoltaic cells, which directly convert sunlight into electricity using semi-conductors (such as silicon) and other suitable semiconductors, have been developed. In addition, due to its almost limitless source, the sun is often used in tandem with other energy sources, such as wind power or thermal power – although these two sources of energy are complementary and, when managed properly, can deliver electricity round-the-clock without relying solely on the sun.
The main limitation of solar energy is that it is reliant on natural phenomena such as the sun shining and the earth being at the right angle for it to reach the ground – meaning that it can be significantly reduced or prevented by factors as simple as cloud cover and shade. Furthermore, depending on where you are in the world, the intensity of sunlight hitting the ground may be significantly reduced, even at midday, which again can reduce the amount of electricity that can be produced. Fortunately, as a result of technological advancements in the field, this limitation is becoming less significant each year.