from cost and production viewpoint.
Figure 2.6 Worldwide, LCOE from the alternative energy sources for the period 2010–2017.
Source: https://www.irena.org/Statistics © IRENA.
Note2: Dashed line represents the global weighted average LCOE and band shows the fossil‐fuel‐fired electricity generation cost range.
2.5.3 Cost‐Effective Production
Globally, levelized cost of electricity (LCOE) from solar and wind energy is decreased by a large factor from 2010 to 2017 as depicted in Figure 2.6. Electricity production from other energy sources has not realized any major change. In fact, global weighted average LCOE as represented by the dashed line in Figure 2.6 has increased for geothermal and hydropower while for biomass it remains the same for the period from 2010 to 2017.
Onshore and offshore wind technologies are competitive to fossil fuels and in some regions, LCOE from wind energy is less than that from fossil fuels. Electricity production cost from PV is also approaching the cost from fossil fuels. Cost of crystalline PV has reduced by 99.5% in the last 30 years due to tremendous research in PV industry with the development of novel materials and techniques (www.economist.com). As reported by (IRENA 2019a), the global weighted average total installation cost for offshore wind projects will decline in the near future, and it will be USD 1700–3200/kW by 2030 and USD 1400–2800/kW by 2050.
Electricity generation using hydro technology is the most cost‐effective and preferred over the other renewable energy sources method where available. Using gravity water wheel instead of Kaplan turbines in small‐scale hydro plants reduces the cost as the former cost is 33–60% of the latter (Quaranta and Revelli 2018). Further, usage of PATs also decreases the installation cost which leads to overall reduction in electricity generation cost from the small hydro plants as well.
Cost of power generation using geothermal energy largely depends on the site. Normally, cost of geothermal plant lies between USD 1870 and 5050 per kW. Compared with direct dry steam and flash plants, the cost of binary plant is high. The LCOE from a geothermal plant is between USD 0.04 and 0.14 per kWh, assuming maintenance costs of USD 110 per kW per year and a life span of 25 years (IRENA 2017).
2.6 Future: Alternative Sources of Energy
Future of solar energy is very promising especially for solar PV systems such as PV/T, CPV and PV‐powered desalination systems. These systems can be path breaking in solving the hurdles of energy requirement in coming centuries. More R&D is needed in the PV/T and CPV systems to make economically viable at the user end.
Onshore wind energy sector can drive overall renewables growth worldwide due to the availability of abundant wind resource, large and competitive market and cost‐effective technologies owing to advances in the recent times. Moreover, changing policies across the globe will further boost this industry in future. Offshore wind energy sector can have tremendous potential in the next three decades with 10 times increase in its capacity (IRENA 2019g). Figure 2.7 shows the trends in investment in renewable energy, worldwide. Maximum investments in solar and wind sectors indicate a promising future for these two sources. Bioenergy sector is also ahead of other energy sources with respect to investments which displays its prospects in future.
Despite small investments in geothermal, the future of EGS has tremendous potential to expand and contribute more in power generation. By 2050, the installed capacity of EGS electricity production will be 70GWe assuming 85% probability. Due to advances in the area of EGS technology, more EGS power plants will be added, thus making it as one of the emerging technologies in the geothermal power sector. Investments in small hydropower are consistent in the last decade and are relatively small compared with other renewable sources.
Figure 2.7 Global investment in renewable energy.
Source: Modified from Frankfurt School‐UNEP Centre/BNEF (2020). Global Trends in Renewable Energy Investment 2020. https://www.irena.org..
2.7 Conclusions
Recent advances in technology, cost‐effectiveness of power production and ecological effects of all alternative sources of energy are thoroughly deliberated in the chapter. Currently, exploitation of alternative energy sources is small compared with the non‐renewable energy sources. Despite the negligible emission of GHGs, green nature and least impact on environment, renewable energy sources usage are still small. Cost of electricity generation is the main obstacle for harnessing renewable sources which could be fixed through further research. Out of all the alternative sources of energy, the solar and wind sectors are experiencing higher growth due to advances in technologies, reduction in cost and better energy conversion efficiency. Hydropower is a mature technology. New investments are taking place in small hydro plants owing to their environment‐friendly nature. EGS is an emerging technology in the geothermal sector because of developments in drilling technology. Bioenergy sector is also increasing at a consistent pace, however, growth is not rapid as this technology needs more developments with respect to cost‐effectiveness, land usage, economical pre‐treatment methods for lignocellulosic, efficiency increment and policy amendments. In the future, ocean energy can possibly diversify the renewable energy arena by addition in power generation and will become a support to the economy. Hydrogen could be a promising fuel in future as it possesses significant potential. However, its production methods from renewable energy sources are still at primary stage. Commercialization of these processes has a long journey ahead.
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