Sol 650 Z-Cam image inadvertently catches the solitary Mars helicopter as it struggles to stay warm Credits: NASA/JPL-Caltech/ASU/MSSS
Exploring Mars is hazardous work. Robotic missions that are sent there have to contend with extreme temperatures, dust storms, intermittent sunlight, and rough terrain. In recent years, two robotic missions were lost due to dust alone, and all that roving around has done a number on the Curiosity rover’s treads. It’s understandable why mission teams are pleasantly surprised when their missions make it through a rough patch. This was the case with the Ingenuity team when they discovered that the rotorcraft, which has been exploring Mars alongside Perseverance, survived the night and is back in working order.
Testing how robotic helicopters fair in the Martian environment is one of the objectives of Ingenuity, which is the first mission of its kind on Mars. On May 3rd, 2022, the mission team learned that Ingenuity had lost power after trying to keep itself warm during the cold Martian night. Luckily, there was enough sunlight the following morning for the little rotorcraft to power up its batteries again and resume normal operations. This was a welcome relief, given that the Opportunity rover and InSight lander were both lost to the extreme cold and dust that characterize a Martian winter.
Artist's impression of the Caltech Space Solar Power Demonstrator (SSPD), Credit: Caltech
Solar power, long considered the leading contender among renewable energy sources, has advanced significantly over the past few decades. The cost of manufacturing and installing solar panels has dropped considerably, and efficiency has increased, making it price competitive with coal, oil, and fossil fuels. However, some barriers, like distribution and storage, still prevent solar power from being adopted more aggressively. In addition, there’s the ever-present issue of intermittency, where arrays cannot collect power in bad weather and during evenings.
These issues have led to the concept of space-based solar power (SBSP), where satellites equipped with solar arrays could gather solar energy twenty-four hours a day, seven days a week, three-hundred and sixty-five days a year. To test this method, researchers at the California Institute of Technology (Caltech) recently launched a technology demonstrator to space. It’s called the Space Solar Power Demonstrator (SSPD), which will test several key components of SBSP and evaluate the method’s ability to harvest clean energy and beam it back to Earth.
Many space-based technologies are still looking for their “killer app” – the thing that they do better than anything else and makes them indispensable to whoever needs to have that app to solve a problem. At this point in the development of humanity, most of those killer apps will involve solving a problem back on Earth. Space-based solar power satellites are certainly one of those technologies.
They have the potential to fundamentally transform the energy industry here on Earth. But they need that one “killer app” to get people interested in investing in them. A study from a group of researchers at the Colorado School of Mines looked at one potential use case – powering remote mining sites that aren’t connected to any electric grid. Unfortunately, even at those extremes, solar power satellites aren’t yet economical enough to warrant the investment.
Artist impression of a Moon Base concept. Credit: ESA – P. Carril
Within the next decade, several space agencies and commercial space partners will send crewed missions to the Moon. Unlike the “footprints and flags” missions of the Apollo Era, these missions are aimed at creating a “sustained program of lunar exploration.” In other words, we’re going back to the Moon with the intent to stay, which means that infrastructure needs to be created. This includes spacecraft, landers, habitats, landing and launch pads, transportation, food, water, and power systems. As always, space agencies are looking for ways to leverage local resources to meet these needs.
This process is known as in-situ resource utilization (ISRU), which reduces costs by limiting the number of payloads that need to be launched from Earth. Thanks to new research by a team from the Tallinn University of Technology (TalTech) in Estonia, it may be possible for astronauts to produce solar cells using locally-sources regolith (moon dust) to create a promising material known as pyrite. These findings could be a game-changer for missions in the near future, which include the ESA’s Moon Village, NASA’s Artemis Program, and the Sino-Russian International Lunar Research Station (ILRS).
For years, NASA has been gearing up for its long-awaited return to the Moon with the Artemis Program. Beginning in 2025, this program will send the first astronauts (“the first woman and first person of color”) to the Moon since the end of the Apollo Era. Beyond that, NASA plans to establish the necessary infrastructure to allow for a “sustained program of lunar exploration,” such as the Lunar Gateway and the Artemis Base Camp.
Beyond these facilities, several elements are essential to ensuring a long-term human presence on the Moon. These include shelter from the elements, food, air, water, and of course, power. To address this last element, NASA has teamed up with HeroX – the leading crowdsourcing platform – to launch the NASA Watts on the Moon Challenge. This competition is entering Phase II and will award an additional $4.5 million for innovative concepts that supply power to future lunar missions.
Light Bender Artist Concept. Credits: Ronald Neale
In less than three years, astronauts will return to the Moon for the first time since the Apollo Era. As part of the Artemis Program, the purpose is not only to send crewed missions back to the lunar surface to explore and collect samples. This time around, there’s also the goal of establishing vital infrastructure (like the Lunar Gateway and a Base Camp) that will allow for “sustained lunar exploration.”
A key requirement for this ambitious plan is the provision of power, which can be difficult in regions like the South Pole-Aitken Basin – a cratered region that is permanently-shadowed. To address this, a researcher from the NASA Langley Research Center named Charles Taylor has proposed a novel concept known as “Light Bender.” Using telescope optics, this system would to capture and distribute sunlight on the Moon.
It sounds like science fiction, but building an enormous tower several kilometers high on the Lunar surface may be the best way to harness solar energy for long-term Lunar exploration. Such towers would raise solar panels above obstructing geological features on the Lunar surface, and expand the surface area available for power generation.
It is a foregone conclusion that if humanity intends to survive the so-called “Anthropocene” we need to make the transition away from fossil fuels and other methods that are unsustainable and amplify our impact on the planet. In this respect, a great deal of research and development is being directed towards “renewable energy.” Of the many methods that are being developed, the biggest contender is and always has been solar power.
Unfortunately, solar power suffers from a number of drawbacks, like the fact that it is only available during the day and favorable weather conditions. However, a new study by researchers from the Institute for Research in Electronics and Applied Physics (IREAP) shows how a special kind of photovoltaic cell could generate power at night. These “anti-solar” cells could revolutionize renewable energy and make it far more proficient.
Technicians at the DLR's Institute for Solar Research inspecting lamps in the Synlight. Image: DLR/Markus Hauschild.
Hydrogen is the most abundant element in the Universe. But here on Earth, it’s rather rare. That’s unfortunate, because in our warming world, its status as an emissions-free fuel makes it a coveted chemical. If German researchers are successful, their Synlight project will help make renewable hydrogen fuel a reality.
Dubbed the “artificial Sun”, the Synlight uses concentrated light to power Thermochemical Water Splitting (TWS.) Every school child knows you can produce hydrogen by electrolysis—running an electric current through water. But that takes an enormous amount of electricity. TWS might be a better way of getting hydrogen out of water, but it takes an enormous amount of energy too, and that’s what the German research is about.
When combusted with pure oxygen—inside a fuel cell for example—hydrogen’s only waste product is water. No greenhouse gases or particulates are produced. But if we want to use it to power our cars, buses, trucks, and even airplanes, we need enormous amounts of it. And we need to produce it cost-effectively.
“Renewable energies will be the mainstay of global power supply in the future.” – Karsten Lemmer DLR Executive Board Member
The idea is to use the heat generated by Concentrated Solar Power (CSP) to extract hydrogen from water, thereby eliminating the need for electricity. CSP systems use mirrors or lenses to concentrate a large area of sunlight into a small area. The heat from that action can be used to power TWS. The Synlight project in Germany is demonstrating the viability of TWS by mimicking the effect of concentrated sunlight. In doing so, researchers there are building what’s being called the world’s largest artificial Sun.
Each of Synlight’s 149 zenon short-arc lamps can be controlled individually. Image: DLR/Synlight/Markus Hauschild
German researchers at the German Aerospace Center (DLR) at Julich near Cologne built the Synlight, a system of 149, high power lamps of the type used in film projections. When all these lamps are turned on, Synlight produces light that is about 10,000 times more intense than natural sunlight on Earth. When all the lamps are aimed at a single spot, Synlight generates temperatures up to 3000 Celsius. The challenge now is to develop materials and processes that can operate in such an extreme temperature.
The 15m tall Synlight experiment is housed in this building in Julich. The building contains 3 separate radiation chambers for different experiments. Image: DLR CC By 3.0
The Synlight system itself uses an enormous amount of electrical power to operate. But that’s often the case with experimental facilities. The Synlight project will mimic the effect of intense, continuous solar energy, something that is not readily available in Germany. By building a test facility powered by electricity, researchers will be able to reliably perform experiments without being delayed or affected by cloudy weather.
“Fuels, propellants and combustibles acquired using solar power offer immense potential for long-term storage and the production of chemical raw materials, and the reduction of carbon dioxide emissions. Synlight will enhance our research in this field.” – Karsten Lemmer, DLR Executive Board Member
As Johannes Remmel, the North Rhine-Westphalia Minister for Climate Protection, said, “”We need to expand existing technology in practical ways in order to achieve renewable energy targets, but the energy transition will falter without investments in innovative research, in state-of-the-art technologies and in global lighthouse projects like Synlight.”
The DLR is involved in the PS10 solar power tower in Spain. The PS10 is the world’s fist commercial concentrating solar power tower. Image: By afloresm – SOLUCAR PS10, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=2821733
This is not the German Aerospace Center’s first foray in concentrated solar power. They’re involved in a number of projects to advance concentrated solar power and thermal water splitting. The DLR is a partner in the Hydrosol II pilot in Spain. It’s a reactor for solar thermochemical hydrogen production that has been in operation since 2008. They’re also involved in the first commercially operated solar tower plant, an 11 megawatt system in Spain called the PS10 solar power tower.
Artist's concept of a space-based solar array. Credit NASA/SAIC
In recent years, alternative energy has been the subject of intense interest and debate. Thanks to the threat of Climate Change, and the fact that average global temperatures continue to rise year after year, the drive to find forms of energy that will reduce humanity’s reliance on fossil fuels, coal, and other polluting methods has naturally intensified.
While most concepts for alternative energy are not new, it has only been in the past few decades that the issue has become pressing. And thanks to improvements in technology and production, the costs of most forms of alternative energy has been dropping while efficiency has been increasing. But just what is alternative energy, and what is the likelihood of it becoming mainstream?
Definition:
Naturally, there is some debate as to what “alternative energy” means and what it can be applied to. On the one hand, the term can refer to forms of energy that do not increase humanity’s carbon footprint. In this respect, it can include things as nuclear facilities, hydroelectric power, and even things like natural gas and “clean coal”.
Residential solar panels in Germany. Credit: Wikimedia Commons/ Sideka Solartechnik
On the other hand, the term is also used to refer to what are currently considered to be non-traditional methods of energy – such as solar, wind, geothermal, biomass, and other recent additions. This sort of classification rules out methods like hydroelectric, which have been around for over a century and are therefore quite common to certain regions of the world.
Another factor is that alternative energy sources are considered to be “clean”, meaning that they don’t produce harmful pollutants. As already noted, this can refer to carbon dioxide but also other emissions like carbon monoxide, sulfur dioxide, nitrogen oxide, and others. Within these parameters, nuclear energy is not considered an alternative energy source because it produces radioactive waste that is highly toxic and must be stored.
In all cases, however, the term is used to refer to forms of energy that will come to replace fossil fuels and coal as the predominant form of energy production in the coming decades.
Types of Alternative Energy:
Strictly speaking, there are many types of alternative energy. Once again, definitions become a bit of a sticking point, and the term has been used in the past to refer to any method that was considered non-mainstream at the time. But applying the term broadly to mean alternatives to coal and fossil fuels, it can include any or all of the following:
Hydroelectricity: This refers to energy generated by hydroelectric dams, where falling water (i.e. rivers or canals) are channeled through an apparatus to spin turbines and generate electricity.
A nuclear power plant, releasing hot steam as a byproduct of its slow fission process. Credit: Wikipedia Commons/Emmelie Callewaert
Nuclear Power: Energy that is produced through slow-fission reactions. Rods of uranium or other radioactive elements heat water to generate steam, which in turn spins turbines to generate electricity.
Solar Power: Energy harnessed directly from the Sun, where photovoltaic cells (usually composed of silicon substrate, and arranged in large arrays) convert the Sun’s rays directly into electrical energy. In some cases, the heat produced by sunshine is harnessed to produce electricity as well, which is known as solar-thermal power.
Wind Power: Energy generated by air flow, where large wind-turbines are spun by wind to generate electricity.
Geothermal Power: Energy generated by heat and steam produced by geological activity in the Earth’s crust. In most cases, this consists of pipes being placed in the ground above geologically active zones to channel steam through turbines, thus generating electricity.
Tidal Power: Energy generated by tidal harnesses located around shorelines. Here, the daily changes in tides causes water to flow back and forth through turbines, generating electricity that is then transferred to power stations along the shore.
Biomass: This refers to fuels that are derived from plants and biological sources – i.e. ethanol, glucose, algae, fungi, bacteria – that could replace gasoline as a fuel source.
Hydrogen: Energy derived from processes involving hydrogen gas. This can include catalytic converters, where water molecules are broken apart and reunited by electrolysis; hydrogen fuel cells, where the gas is used to power internal combustion engines or heated and used to spin turbines; or nuclear fusion, where atoms of hydrogen fuse under controlled conditions to release incredible amounts of energy.
The Mega Ampere Spherical Tokamak (MAST) reactor at the Culham Centre for Fusion Energy (UK). Credit: CCFE
Alternative and Renewable Energy:
In many cases, alternative sources of energy are also renewable. However, the terms are not entirely interchangeable, owing to the fact that many forms of alternative energy rely on a finite resource. For instance, nuclear power relies on uranium or other heavy elements that must be mined.
Meanwhile, wind, solar, tidal, geothermal and hydroelectric power all rely on sources that are entirely renewable. The Sun’s rays are the most abundant energy source of all and, while limited by weather and diurnal patters, are perennial – and therefore inexhaustible from an industry standpoint. Wind is also a constant, thanks to the Earth’s rotation and pressure changes in our atmosphere.
Development:
Currently, alternative energy is still very much in its infancy. However, this picture is rapidly changing, owing to a combination of political pressure, worldwide ecological disasters (drought, famine, flooding, storm activity), and improvements in renewable energy technology.
For instance, as of 2015, the world’s energy needs were still predominantly provided for by sources like coal (41.3%) and natural gas (21.7%). Hydroelectric and nuclear power constituted 16.3% and 10.6%, respectively, while “renewables” (i.e. solar, wind, biomass etc.) made up just 5.7%.
In Denmark, wind power accounts for 28% of electrical production and is cheaper than coal power. Credit: denmark.dk
This represented a significant change from 2013, when the global consumption of oil, coal and natural gas was 31.1%, 28.9%, and 21.4%, respectively. Nuclear and hydroelectric power made up 4.8% and 2.45, while renewable sources made up just 1.2%.
In addition, there has been an increase in the number of international agreements regarding the curbing of fossil fuel use and the development of alternative energy sources. These include the Renewable Energy Directive signed by the European Union in 2009, which established goals for renewable energy usage for all member states for the year of 2020.
Basically, the agreement stated that the EU fulfill at least 20% of its total energy needs with renewables by 2020, and that at least 10% of their transport fuels come from renewable sources by 2020. In November of 2016, the European Commission revised these targets, establishing that a minimum of 27% of the EUs energy needs come from renewables by 2030.
In 2015, the United Nations Framework Convention on Climate Change (UNFCCC) met in Paris to come up with a framework for greenhouse gas mitigation and the financing of alternative energy that would go into effect by 2020. This led to The Paris Agreement, which was adopted on December 12th, 2015 and opened for signatures on April 22nd (Earth Day), 2016, at the UN Headquarters in New York.
The Krafla a geothermal power station located i0n Iceland. Credit: Wikipedia Commons/Ásgeir Eggertsson
Several countries and states have also been noted fore their leadership in the field of alternative energy development. For instance, in Denmark, wind power provides up to 140% of the country’s demand for electricity, with the surplus being provided to neighboring countries like Germany and Sweden.
Iceland, thanks to its location in the North Atlantic and its active volcanoes, achieved 100% reliance on renewable energy by 2012 through a combination of hydroelectricity and geothermal power. In 2016, Germany’s policy of phasing out reliance on oil and nuclear power resulted in the country reaching a milestone on May 15th, 2016 – where nearly 100% of its demand for electricity came from renewable sources.
The state of California has also made impressive strides in terms of its reliance on renewable energy in recent years. In 2009, 11.6 percent of all electricity in the state came from renewable resources such as wind, solar, geothermal, biomass and small hydroelectric facilities. Thanks to multiple programs that encourage switching to renewable energy sources, this reliance increased to 25% by 2015.
Based on the current rates of adoption, the long-term prospects for alternative energy are extremely positive. According to a 2014 report by the International Energy Agency (IEA), photovoltaic solar power and solar thermal power will account for 27% of global demand by 2050 – making it the single largest source of energy. Similarly, a 2013 report on wind power indicated that by 2050, wind could account for up to 18% of global demand.
The IEA’s World Energy Outlook 2016 also claims that by 2040, natural gas, wind and solar will eclipse coal and oil as the predominant sources of energy. And some even go as far to say that – thanks to developments in solar, wind, and fusion power technology – fossil fuels will become obsolete by 2050.
As with all things, the adoption of alternative energy has been gradual. But thank to the growing problem of Climate Change and rising demand for electricity worldwide, the rate at which clean and alternative methods are being adopted has become exponential in recent years. Sometime during this century, humanity may reach the point of becoming carbon neutral, and not a moment too soon!
