RE is Growing
Shares of Renewable Energy Throughout the World
Renewable energy (RE) sources currently account for over ¼ of the electricity generated in the global electricity mix, as an overall average between all RE sources combined (29.3% of global electricity was from RE as of 2022, and that figure is projected to grow substantially - see the 'Green Scenario" chart from BNEF below - solar and wind are growing rapidly).
Solar farms, wind farms, hydroelectric dams (and other hydrokinetic projects), (as well as a relatively small share of biomass plants and geothermal plants) have the potential to deliver the majority of the world's energy needs - depending on how much investment these RE sources receive.
Dropping prices for renewable energy, and favorable policies for renewables, have seen the share of RE for electricity generation rise rapidly in many countries throughout Europe, North America, Asia, Latin America, and the rest of the world.
RE sources (especially solar and wind) are the majority of new power additions to countries' electrical generating capacity throughout much of the world.
In its World Energy Outlook (WEO), the International Energy Agency (IEA) identifies pathways for clean energy technological solutions (with RE as the main solution) needed to reach global net zero greenhouse gas emissions (net zero GHGs) by 2050. It also details interim goals that will ensure the world is on the path to carbon neutrality.
In order to achieve the 2050 net zero goal, zero and low-carbon energy sources, largely RE sources, need to generate almost all of the world's electricity by mid-century.
Global low-carbon energy needs to rise to become a vast majority of the global energy mix, up from 38.5% of global electricity for RE + nuclear combined in 2022 (the net zero goal includes nuclear as a needed energy source, as nuclear produces virtually zero emissions besides water vapor - nuclear provided 9.2% of the world's electricity in 2022).
The US, the UK, the EU (and many European nations individually), Canada, Japan, and Australia, among other countries, have mandated their countries reach net zero by 2050 (Sweden and Germany aim for net zero emissions by 2045). China aims for net zero by 2060, and India has a goal of reaching net zero by 2070.
Countries throughout Europe invest in significant development of renewable energy technologies and have substantial generation from RE sources.
Many European countries; especially Northern European nations; led by Norway (almost 100%, mostly hydroelectricity), Sweden (over 65%), Iceland (almost 100%, from hydroelectricity and geothermal), Germany (over 50%), Denmark (over 60%), and the United Kingdom (over 40%) - have a large share of renewable energy production in their electricity mix. These countries are above the European average of almost 40% of electricity sourced from RE.
The United States generates over 20% of its electricity from renewable energy sources (21.3% as of October 2023). Many states have renewable portfolio standards (RPS) that require those states to generate a specified amount of their energy from renewables.
Canada generates over 65% of its electricity from RE sources (predominantly hydroelectricity). Some Canadian provinces generate a much larger share of electricity from RE. British Columbia gets around 95% of its electricity from RE (thanks to a large share of hydroelectricity).
Many Latin American countries produce a significant amount of renewable energy for electricity; around 50% as an overall rough average of the majority of Latin American countries' overall energy mix; though some countries in Latin America produce much higher shares of renewable energy. For example, Brazil produces over 80% RE for electricity (due to a large share of hydroelectricity). Costa Rica is powered almost entirely by RE.
China produces over ¼ of its electricity from RE sources (despite having a much higher share of RE generating capacity). Meanwhile, India has a renewable energy capacity of over ⅓ of its total installed energy capacity, however, around 80% of its electricity generation is still from fossil fuels.
It must be noted that the amount of renewable energy generation varies widely from country to country, and from region to region within countries. States and provinces within countries have wide variations of renewable energy generation as a share of a country's energy mix, and have varying mandates for future renewable energy production.
For example, in the United States, California produces over 40% of its energy from renewable sources, and is under a statewide mandate to get 100% of its electricity from clean energy sources by 2045.
Falling Cost of Solar and Wind
Wind and solar are now less expensive than fossil fuels and have also reached high levels of efficiency recently. For reference, below is Lazard‘s levelized cost of energy (LCOE) chart - showing that RE (especially onshore wind farms and utility-scale solar) has become the lowest-cost energy option.
On the LCOE chart, it’s onshore wind farms and utility-scale solar photovoltaics (PV) with the best (or tied for the best) overall prices of all energy sources.
Onshore wind and utility-scale PV are now priced much lower than coal (about ½ the LCOE). Both onshore wind and utility-scale PV are now cheaper than gas combined cycle (when the full LCOE is taken into account, and in certain circumstances)>>>
Future Expansion of RE
Bloomberg New Energy Finance (BNEF) illustrates the projected rise of solar and wind in the below chart (a chart of global installed RE capacity...global RE generation should ideally mirror the trend seen in capacity markets). While solar and wind are projected to expand significantly, hydroelectric capacity is projected to remain constant.
Wind and solar are quickly growing, and will soon dominate the global RE market (hydro is currently the dominant form of global RE). In fact, in the United States, wind (at just over 10% of total electricity generation in 2022) has already overtaken hydro (at just over 6%) as the dominant form of RE. In much of Europe, wind has long surpassed hydro in the RE generation market.
Below is a chart of RE's rise to mid-century in BNEF's green scenario, especially solar and wind, and a few of BNEF's top-line takeaways from their energy outlook to 2050>>>
"1. Wind and solar make up almost 50% of world electricity in 2050 – “50 by 50” – and help put the power sector on track for 2 degrees to at least 2030.
2. A 12TW expansion of generating capacity requires about $13.3 trillion of new investment between now and 2050 – 77% of which goes to renewables.
3. Europe decarbonizes furthest, fastest. Coal-heavy China and gas-heavy U.S. play catch-up.
4. Wind and solar are now cheapest across more than two-thirds of the world. By 2030 they undercut commissioned coal and gas almost everywhere."
[FROM: bnef.com/new-energy-outlook]
Sources of Renewable Energy
Sources of renewable energy include hydroelectric energy (and hydrokinetic energy), wind (onshore and offshore), solar (PV and solar thermal technologies), biomass (and biofuels), and geothermal. These 5 renewable energy sources are summarized below, starting with hydroelectricity>>>
Hydroelectricity
The largest single source of renewable energy worldwide is hydroelectricity, mostly from hydroelectric dams. Hydropower represents a significant portion of total overall world RE production - about 60% of the world's renewable electricity generation is from hydroelectricity (and in the U.S., about 35% of all renewable electricity generation is from hydroelectricity).
As far as electricity consumption originating from hydroelectricity, around 15% of the world's electricity needs are met by hydroelectricity (around 6% in the U.S.).
In the United States, renewable energy represents about 20% of total energy generation as an overall average of all 50 states, although Washington state gets over 60% of its electricity from hydroelectric dams alone. Hydroelectricity represents just over 6% of total U.S. electricity generation (as a total average when all the states are factored in).
Dams can easily be installed in almost any waterway, including rivers in remote rural areas. A reservoir (water from a river, lake, or another waterway) is let through a hydroelectric dam by the dam's operators when it's time to generate electricity.
The kinetic energy of the water flowing through the dam turns turbines, which generate electricity. Although hydroelectric dams have proven to be a reliable energy source, dams do present myriad issues.
Dams, both large and smaller scale, produce some ecological problems and require constant maintenance. Dams do tend to result in large reservoirs of stagnant water, erosion of wetlands, and erosion of areas surrounding the dam, along with other problems for the local ecosystems downstream from where dams are developed.
Hydrokinetic systems are in use in freshwater lakes and rivers, as well as oceans, throughout the world today. Freshwater tidal energy and currents; as well as ocean waves, currents, and tides, also represent dynamic, abundant sources of renewable energy.
These RE sources are environmentally friendly; as long as care for the affected ecosystems is implemented and maintained by the RE developers.
The most common types of these freshwater hydrokinetic systems include tidal barrages and tidal stream generators. Ocean sources of hydropower remain in the research and development phase and have reached the demonstration phase for a few projects worldwide...
Please see:
Wind
Wind power is generated with the conversion of energy by wind turbines into electricity (the kinetic energy of wind turns electricity-generating turbines). Wind farms are installed on uninhabited land, unused desert land, agricultural land, or offshore (most offshore wind farms are currently in Northern European countries).
Wind farms have some of the lowest environmental impacts of all large-scale renewable energy sources.
Wind is the source of over 7% of the world's electricity needs (over 20% of global electricity generation from RE sources), and that number is rapidly climbing. In the United States, over 10% of electricity needs are met by wind, and in countries in Europe, the average for wind is over 14%.
Some European countries generate a much higher share of wind energy for their electricity needs. For example, the U.K., Germany, Sweden, the Netherlands, Finland, Belgium, and Denmark, generate around a quarter of their electricity from wind power.
Large-scale wind farms are much more common than units for individual homes. Smaller wind turbine units are increasing in production, however, and are capable of powering anything from large appliances or generators, to RVs, to entire buildings; depending on the size of the turbine.
Please click & read:
Breakthroughs in wind energy technology
London Array – paving the way for efficient offshore wind energy farms
Anholt Offshore Wind Farm — Denmark’s most powerful source of renewable energy
The Block Island Wind Farm – America’s 1st operational offshore wind farm
It must be noted that employment opportunities in clean and renewable energy, especially wind and solar, are consistently growing; while the cost of RE is decreasing, and the efficiency of clean energy continues to increase.
Solar
Photovoltaic (PV) solar power entails harnessing the sun's energy to directly produce electricity by converting sunlight into electricity through solar PV cells (the "photovoltaic effect").
New solar technologies are developing at a rapid pace, bringing the cost of community solar and some rooftop solar to reach cost parity with coal and some gas energy generation. Some solar PV is now priced below the cost of fossil fuels (in the cases of utility-scale thin-film PV and utility-scale crystalline PV).
Solar cells are becoming more efficient, thinner, smaller, transportable, and flexible (even spray-on designs are in R&D). This allows for easy installation, use, and efficient energy production. Solar PV cells, solar panels, solar microgrids, and solar farms, have been used to power a wide range of applications.
Solar technologies are used in everything from the calculator powered by a single solar cell, to off-grid homes powered by an entire photovoltaic array; to solar farms powering thousands of homes and buildings in a city. Large-scale, or mega, solar farms are growing in deployment worldwide.
Concentrated Solar Power (CSP), solar towers, and parabolic dishes and troughs, are all growing sources of renewable energy (solar thermal energy sources). Solar water heaters are also a form of solar thermal energy.
As opposed to PV, which directly generates electricity, solar thermal uses solar energy indirectly, to heat a working fluid.
Solar thermal, including CSP and parabolic solar (among a few other forms of solar thermal), uses technology (in CSP that's special mirrors for solar energy creation - heliostats) to harness the sun's energy; but then that energy heats a working fluid, which is ultimately used to generate electricity (traditionally the energy production takes the form of steam that turns turbines, as in many other forms of energy generation).
One benefit of solar thermal is that a few forms of energy storage are readily available when this form of renewable energy is employed (such as thermal energy storage).
Please click & read:
Recent breakthroughs in solar photovoltaic and solar thermal technologies
Community solar and net metering – pushing renewable energy forward
Ivanpah Solar Electric Generating System
The 550-megawatt Topaz Solar Plant
Biomass
Biomass includes food crops that easily convert to energy like corn, sugarcane, wheat, soybean, palm, and sorghum.
(2nd-generation) Biomass sources also include agricultural by-products, forestry remnants, as well as other organic matter (this category of biomass includes crop residues, agricultural waste, other waste streams, wood chips, peat, and bark). Sources of biomass also include non-food energy crops such as switchgrass (2nd generation biomass) and various types of algae (algae is considered a 3rd-generation biomass source).
Biomass includes organic matter and biodegradable wastes that can be used as biofuel (ethanol and biodiesel). Biomass can produce energy for a municipality in a biomass power plant, be converted into biofuel, or even power a farm (see the link to anaerobic digestion below).
Biomass/ biofuel can be derived from numerous types of organic cellulosic plants (energy crops such as switchgrass), in addition to waste (municipal waste, agricultural residues, forestry remnants, etc...).
Using cellulosic feedstocks is a way to avoid using crops needed for food, and also represent readily available or easy-to-produce feedstocks. Cellulosic biomass feedstocks are abundant, inexpensive, non-food sources for biomass/ biofuel energy production.
Many varieties of plant species can be used for biomass/ biofuel production, however, algae is an especially promising biomass source. Algae are among the fastest-growing plants in the world, and as much as 60% of their weight is plant-based oil - making algae a potent source for energy generation.
Please see:
Anaerobic digestion - a proven solution to our waste problem
Cellulosic biofuel - fuel solutions
Geothermal
Geothermal power also has small and large-scale designs. Geothermal heat pumps, on the small end of the spectrum, are less common than industrial geothermal power plants.
Geothermal plants are located near natural energy sources; tectonic plate boundaries, volcanoes, hot springs, and geysers. Geothermal energy is primarily power generated from natural steam and hot rocks, magma, or lava which heat water underground in the earth's crust.
The majority of geothermal power is produced by conveying heated water or steam back to the surface so that its heat can be extracted through a heat exchanger, or its pressure can be used to drive turbines. An example of an area of the world rich in geothermal energy potential, production, and use is Iceland.
Please see:
Geothermal district heating in Iceland
Of course, there are a few other potential RE sources, including forms of kinetic renewable energy and futuristic RE ideas not mentioned above. Other types of RE in research and development today include, most notably, green hydrogen and hydrogen fuel cells, although the main type used today is 'grey' hydrogen for industrial applications.
Grey hydrogen is sourced from fossil fuels for use in fossil fuel-intensive industries. 'Green' and 'blue' hydrogen (green is made with RE and blue is made using carbon capture) can potentially, eventually, be used to help meet the world's low carbon energy needs.
More R&D is needed for the rest of Europe, the USA, and Australia (among other countries in Asia and elsewhere that have shown an active interest in hydrogen fuel cells), to use hydrogen/ hydrogen fuel cells efficiently and effectively as a major energy source. However, there are already significant hydrogen fuel cell bus projects in some European countries.