Introduction The heated debate about the dangerous effects that come from the continued use of fossil fuels as the main sources of energy has resulted in a number of recommendations (Kowalski 5). Among the recommendations is the suggestion for other sources of energy, instead of the fossil fuels. These are known as alternative energy sources. As of today, a lot of resources are being diverted to projects and programs that aim at popularizing alternative energy sources not only at household level, but also at the industrial level. However, the most important question when it comes to the different forms of renewable energy that have been devised concerns the sustainability of these forms of energy in terms of the quantity and minimal impacts on the environment. This paper argues that the alternative forms of energy seem not to offer a perfect solution to the demands of energy in the contemporary world. The paper explores alternative energy. It also focuses on the pros and cons, as well as the contemporary and future developments concerning the subject of alternative energy. Understanding the issue of alternative energy It is common to hear a lot of people mention the topic of alternative energy when it comes to the issue of sustainable development. Alternative energy sources are sources of energy that are different from fossil fuels. For a long time, fossil fuels have been highly deployed in the production of energy. However, concerns have been raised about the level of pollution in the environment that is caused by the increased emission of greenhouse gases, like carbon dioxide, which harm the environment. Greenhouse gases are broadly classified into two. These are chlorofluorocarbons and hydrochlorofluorocarbons (Metz 165). A larger percentage of greenhouse gases in the atmosphere are emitted from the burning of fossil fuels. It is important to note that the subject of sustainable development brings into picture the realities about the dangers of continued use of non-renewable forms of energy, the most common being fossil fuels. Therefore, most people agree with the argument that it is important to tap energy from alternative sources. Different from the non-renewable forms of energy, most of the alternative sources of energy are renewable. This is an aspect that embraces sustainability. Common alternative energy sources include hydroelectric energy, solar energy, geothermal energy, wind energy, biomass energy, and nuclear energy. However, Hore-Lacy and Hore-Lacy (7) observe that there is a volatile discussion about the efficient development and use of nuclear energy to generate power. The debate emanates from the politicisation of nuclear energy. Research shows that billions of dollars have already been pumped into different projects as part of the global initiative of minimizing the use of non-renewable forms of energy, while ensuring that the energy production meets the energy demand. In this sense, it is important to mention that the index of industrial growth globally is quite high. This indicates the increased demand for energy. Therefore, the most critical question that needs to be answered at this juncture concerns the ability of people to balance between reductio