I've been watching YouTube videos about energy, where it comes from, how we "make" it, transport it, and use it. The story is almost heroic, but definitely atrocious.
A Little History
In the beginning there were people and an occasional lightning strike hitting a tree and the resulting fire. That wasn't useful, but it was probably terrifying. Later, people found a way to make fire and use it to cook meat. Bar-B-Que was invented. As simple as that sounds, it was a huge leap forward for people who were mostly hunting for nuts & berries and maybe a fish to spear for sushi. This probably occurred on the African continent along the shores.
From Wikipedia: "Claims for the earliest definitive evidence of control of fire by a member of Homo range from 1.7 to 2.0 million years ago (Mya). Evidence for the "microscopic traces of wood ash" as controlled use of fire by Homo erectus, beginning some 1,000,000 years ago, has wide scholarly support. Flint blades burned in fires roughly 300,000 years ago were found near fossils of early but not entirely modern Homo sapiens in Morocco. Fire was used regularly and systematically by early modern humans to heat treat silcrete stone to increase its flake-ability for the purpose of toolmaking approximately 164,000 years ago at the South African site of Pinnacle Point. Evidence of widespread control of fire by anatomically modern humans dates to approximately 125,000 years ago.
As man traveled along the shores to the north-east into what today we call the Middle-East, they somehow invented farming. Bread became king! Being able to farm meant they didn't have to keep moving with herds of animals or staying only along the shores where they could fish. It might also have meant they could stay together with more other people for safety. This discovery of farming sounds like a much bigger thing than fire and it probably has to be seen that way because it enabled people to create cities and to move around the globe to settle better farm lands.
From Wikipedia: "The history of agriculture records the domestication of plants and animals and the development and dissemination of techniques for raising them productively. Agriculture began independently in different parts of the globe, and included a diverse range of taxa. At least eleven separate regions of the Old and New World were involved as independent centers of origin.
Wild grains were collected and eaten from at least 105,000 years ago. However, domestication did not occur until much later. Starting from around 9500 BC..."
Mankind has existed a long time compared to the length of one human life. But, in the early days progress was slow. 125,000 years ago for fire and 100,000 years ago for farming and then how long until the use of modern fuels for machines? For a long time domestication of animals led people to use oxen and horses or mules to pull wagons full of people and/or food crops. Using enslaved people wasn't very common, but they were treated like animals. The last major well-known use of slaves was in the United States and ended with the American Civil War and the Emancipation of slaves. From 100,000 years ago to 1865, 156 years ago, is a long time for changes to happen.
Fortunately the end of slavery was enabled by the creation of a machine to burn a fuel and produce steam which could spin a turbine or turn a steamboat paddle-wheel or a train engine's wheels. It made raw fuel and machines the new slave of capitalism.
From Wikipedia: "A steam engine is a heat engine that performs mechanical work using steam as its working fluid. The steam engine uses the force produced by steam pressure to push a piston back and forth inside a cylinder. This pushing force can be transformed, by a connecting rod and flywheel, into rotational force for work. The term "steam engine" is generally applied only to reciprocating engines as just described, not to the steam turbine. Steam engines are external combustion engines, where the working fluid is separated from the combustion products. The ideal thermodynamic cycle used to analyze this process is called the Rankine cycle. In general usage, the term steam engine can refer to either complete steam plants (including boilers etc.), such as railway steam locomotives and portable engines, or may refer to the piston or turbine machinery alone, as in the beam engine and stationary steam engine.
Although steam-driven devices were known as early as the aeolipile in the first century AD, with a few other uses recorded in the 16th and 17th century, Thomas Savery is considered the inventor of the first commercially-used steam powered device, a steam pump that used steam pressure operating directly on the water. The first commercially successful engine that could transmit continuous power to a machine was developed in 1712 by Thomas Newcomen. James Watt made a critical improvement by removing spent steam to a separate vessel for condensation, greatly improving the amount of work obtained per unit of fuel consumed. By the 19th century, stationary steam engines powered the factories of the Industrial Revolution. Steam engines replaced sails for ships on paddle steamers, and steam locomotives operated on the railways."
Also from Wikipedia: "James Watt was a Scottish inventor, mechanical engineer, and chemist who improved on Thomas Newcomen's 1712 Newcomen steam engine with his Watt steam engine in 1776, which was fundamental to the changes brought by the Industrial Revolution in both his native Great Britain and the rest of the world."
Is it any wonder that The United States of America was declared in 1776. That was a major turning point in the world of science, technology, and politics.
Energy Basics
Energy is a funny thing. We eat foods and our bodies turn that into energy that lets us go out and find or grow more food, so we can keep going. Our bodies aren't like robots that will continue forever, but with better nutrition we have more than doubled the median lifespan of man. In the early 1700s a person could expect to die in childbirth, life to about 35, or be lucky and live into their 80s. Today we rarely die in childbirth and the typical lifespan is probably 80, with some living to 100. We also have much more healthy energetic lives into our later years. In the 1940s a working man was expected to work until 60 and then die at about 65. Today we can retire at 60-65 and live 30 more years. That's a big difference. But, where does energy come from?
Food requires water, air, and sunlight to grow. The earth revolves in a grip with the sun based on falling to the force of gravity and we on Earth are also in the grip of gravity. The tides are changed by the gravity of the moon. The sun provides radiation which becomes light and heat when it interacts with the atmosphere of Earth. There are sound, elasticity, chemical, kinetic (things in motion), magnetism, and nuclear forces. Surely with all that we can use anything with ease, right? Not really.
The force of gravity on water causes it to rain down and not sideways and from the rivers it moves down to the sea. We tame that with a hydro-electric dam to make electricity and this is extremely efficient - perhaps 90% efficient. But, we can't move the river to the people, we can't control how much water comes from the sky or when, and we can't put the water back up in the sky and we can't make it rain in the desert. Gravity is fine coming down, but putting things back up there takes energy. In fact there is a very real modern battery based on storing gravitational potential.Some forms of energy are weak. Sound, elasticity, magnetic, and most chemical forces are insufficient for our purposes. Nuclear, on the other hand, has very great power with the strong nuclear force, but the weak nuclear force is too weak to achieve much. Nuclear force is also somewhat dangerous, so we generally stick to easier fuels.
That brings us to the Industrial Revolution, steam
power, and burning fuels like wood, peat, coal, or oil to get heat. Heat
boils water which produces steam and that turns a grist-mill wheel to
grind grain. But also an automobile wheel or turbine to make
electricity. That is the energy system we know best and that is Industrial Revolution Part II.
Electricity
From Wikipedia: "Long before any knowledge of electricity existed, people were aware of shocks from electric fish. Ancient Egyptian texts dating from 2750 BCE referred to these fish as the "Thunderer of the Nile" ".
Like all the other advances, this one began long before most people know and many different scientists worked with them to produce better understanding and technologies.
Also from Wikipedia:
Electricity would remain little more than an intellectual curiosity for millennia until 1600, when the English scientist William Gilbert wrote De Magnete, in which he made a careful study of electricity and magnetism, distinguishing the lodestone effect from static electricity produced by rubbing amber. He coined the New Latin word electricus ("of amber" or "like amber", from ἤλεκτρον, elektron, the Greek word for "amber") to refer to the property of attracting small objects after being rubbed. This association gave rise to the English words "electric" and "electricity", which made their first appearance in print in Thomas Browne's Pseudodoxia Epidemica of 1646.
Further work was conducted in the 17th and early 18th centuries by Otto von Guericke, Robert Boyle, Stephen Gray and C. F. du Fay. Later in the 18th century, Benjamin Franklin conducted extensive research in electricity, selling his possessions to fund his work. In June 1752 he is reputed to have attached a metal key to the bottom of a dampened kite string and flown the kite in a storm-threatened sky. A succession of sparks jumping from the key to the back of his hand showed that lightning was indeed electrical in nature. He also explained the apparently paradoxical behavior of the Leyden jar as a device for storing large amounts of electrical charge in terms of electricity consisting of both positive and negative charges.
One could easily argue the Leyden jar was a capacitor or battery of sorts, though it was used only for science experiments.
From Wikipedia: "Michael Faraday was an English scientist who contributed to the study of electromagnetism and electro-chemistry. His main discoveries include the principles underlying electromagnetic induction, diamagnetism and electrolysis [ around 1822 https://spectrum.ieee.org/200-years-ago-faraday-invented-the-electric-motor ]
Although Faraday received little formal education, he was one of the most influential scientists in history. It was by his research on the magnetic field around a conductor carrying a direct current that Faraday established the basis for the concept of the electromagnetic field in physics. Faraday also established that magnetism could affect rays of light and that there was an underlying relationship between the two phenomena. He similarly discovered the principles of electromagnetic induction and diamagnetism, and the laws of electrolysis. His inventions of electromagnetic rotary devices formed the foundation of electric motor technology, and it was largely due to his efforts that electricity became practical for use in technology.
Faraday was an excellent experimentalist who conveyed his ideas in clear and simple language; his mathematical abilities, however, did not extend as far as trigonometry and were limited to the simplest algebra. James Clerk Maxwell took the work of Faraday and others and summarized it in a set of equations which is accepted as the basis of all modern theories of electromagnetic phenomena. On Faraday's uses of lines of force, Maxwell wrote that they show Faraday "to have been in reality a mathematician of a very high order – one from whom the mathematicians of the future may derive valuable and fertile methods." The SI unit of capacitance is named in his honour: the farad"
Albert Einstein kept a picture of Faraday on his study wall, alongside pictures of Arthur Schopenhauer and James Clerk Maxwell. Physicist Ernest Rutherford stated, "When we consider the magnitude and extent of his discoveries and their influence on the progress of science and of industry, there is no honour too great to pay to the memory of Faraday, one of the greatest scientific discoverers of all time."
The Steam Turbine and Generating Electricity
A steam turbine is a machine that extracts thermal energy from pressurized steam and uses it to do mechanical work on a rotating output shaft. Its modern manifestation was invented by Charles Parsons in 1884. Fabrication of a modern steam turbine involves advanced metalwork to form high-grade steel alloys into precision parts using technologies that first became available in the 20th century; continued advances in durability and efficiency of steam turbines remains central to the energy economics of the 21st century.
The steam turbine is a form of heat engine that derives much of its improvement in thermodynamic efficiency from the use of multiple stages in the expansion of the steam, which results in a closer approach to the ideal reversible expansion process. Because the turbine generates rotary motion, it is particularly suited to be used to drive an electrical generator—about 85% of all electricity generation in the United States in the year 2014 was by use of steam turbines.
So, Faraday's study of electricity and electro-magnetism in the early 1800s led the way for the development of an electricity generator by 1884 and that has been the major method used to generate electricity in America. Even with only 10% efficiency, it allows a steady supply as long as there is fuel coal and oil. In recent years natural gas has been added to the fuel supply mix while coal is being reduced.
Though electricity generators driven by steam pushing turbines are very inefficient, about 10%, and the modern automobile using an internal combustion engine (ICE) is at about 30%, the induction engine as used in the Tesla EV automobiles are much more efficient [ Tesla EVs: 2003 - today ].
From Wikipedia: "Full-load motor efficiency is around 85–97%," [ for the Tesla electric induction engine ]
Thus, from 1820 to 2003 (183 years) the understanding of electricity and electro-magnetism were developed to produce the steam engine, the steam turbine electricity generator, and more recently the "overnight sensation" Tesla automobile.
Internal Combustion Engine to move Cars
Americans have had a love affair with ICE automobiles. They've given us incredible mobility and enabled trucks to deliver goods nation-wide. Automobiles are about 30% efficient, though large trucks using diesel fuel may be 45% and jet airplanes may be 70% efficient. The truck and jet airplane has taken a great deal of the transportation load from diesel-burning trains and barges, though for some things the slow-moving barge or train transportation is still much cheaper.
https://www.maritime-executive.com/article/barge-transport-wins-on-fuel-efficiency
From Wikipedia: "An internal combustion engine (ICE) is a heat engine in which the combustion of a fuel occurs with an oxidizer (usually air) in a combustion chamber that is an integral part of the working fluid flow circuit. In an internal combustion engine, the expansion of the high-temperature and high-pressure gases produced by combustion applies direct force to some component of the engine. The force is applied typically to pistons, turbine blades, a rotor, or a nozzle. This force moves the component over a distance, transforming chemical energy into useful kinetic energy and is used to propel, move or power whatever the engine is attached to. This replaced the external combustion engine for applications where weight or size of the engine is important.
The first commercially successful internal combustion engine was created by Étienne Lenoir around 1860 and the first modern internal combustion engine was created in 1876 by Nicolaus Otto (see Otto engine)."
A lot was happening during the late 1800s (called the Victorian Era in England or La belle époque in France. In America the first half of the 1800s was leading to our Civil War and it was only the period after the Civil War up to the mid-1900s and World War II which was equivalent. Our Roaring '20s probably epitomized it best. After that period of time, and two world wars, America had new energy and became a world-class power. The vast majority of the automobiles on our highways today still use the internal combustion engine.
As you can see, we have primarily burned fuels for their chemical energy converted to heat for steam to turn a wheel, but then the added use of a turbine to generate electricity was a powerful innovation and homes could be heated or cooled and water could be heated. These make about 2/3rds of all the power plant generated electricity. The diesel-powered train and barge and then the internal-combustion engine for automobiles made things move. Heat was at the heart of these and a lot of it is wasted. Power plants lose a lot of energy to heat. ICE car engines lose a lot of energy to heat. Badly constructed homes lose heat through cracks, windows, roofs, etc. Even electricity transmission lines lose a few percentage points of energy as heat to the air. Appliances in homes were also very inefficient. There has been an energy conservation movement to improve homes and appliances, but the power plants still waste a lot and ICE cars have been improved to their maximum. This brings us to the latest generation in our quest to learn about energy and ways to use it efficiently. It relates to our demands and our demands during this time period were for microcomputers and portability.
The Integrated Circuit for Computers
From Wikipedia: "An integrated circuit or monolithic integrated circuit (also referred to as an IC, a chip, or a microchip) is a set of electronic circuits on one small flat piece (or "chip") of semiconductor material, usually silicon. Large numbers of tiny MOSFETs (metal–oxide–semiconductor field-effect transistors) integrate into a small chip. This results in circuits that are orders of magnitude smaller, faster, and less expensive than those constructed of discrete electronic components. The IC's mass production capability, reliability, and building-block approach to integrated circuit design has ensured the rapid adoption of standardized ICs in place of designs using discrete transistors. ICs are now used in virtually all electronic equipment and have revolutionized the world of electronics. Computers, mobile phones, and other digital home appliances are now inextricable parts of the structure of modern societies, made possible by the small size and low cost of ICs such as modern computer processors and microcontrollers."
We found ways to miniaturize electronics and then realized a portable version of their desktop computer would be very nice. Someone had to begin working on energy-storing batteries which were also small enough and powerful enough to run computers. They use a lot less electricity than their larger former-selves. But, a natural side-effect has been that a lot more people have them and that means overall more electricity is still being used.
Early Devices
"Electricity really ushered in the era of the device. The radio (1893, USA), washing machines (1900, USA), the refrigerator (1922, Sweden), the dishwasher (1924, USA), the television (1927, USA), the electric calculator (1957, Japan), the external (1950, Canada) and internal (1958, Sweden) artificial pacemaker, and literally dozens, if not hundreds more categories, " -- https://odannyboy.medium.com/the-history-of-devices-9b3b57b235f6From Wikipedia: "An electronic calculator is typically a portable electronic device used to perform calculations, ranging from basic arithmetic to complex mathematics.
The first solid-state electronic calculator was created in the early 1960s. Pocket-sized devices became available in the 1970s,"
In my last year of high school I was introduced to the "pocket calculator". I had just bought a traditional slide rule and in class at school someone had a 4-function calculator which would fit in your hand. It was a paradigm change. I never used the slide rule.
The Microcomputer
A microcomputer is a small, relatively inexpensive computer with a microprocessor as its central processing unit (CPU). It includes a microprocessor, memory and minimal input/output (I/O) circuitry mounted on a single printed circuit board (PCB). Microcomputers became popular in the 1970s and 1980s with the advent of increasingly powerful microprocessors. The predecessors to these computers, mainframes and minicomputers, were comparatively much larger and more expensive (though indeed present-day mainframes such as the IBM System z machines use one or more custom microprocessors as their CPUs). Many microcomputers (when equipped with a keyboard and screen for input and output) are also personal computers (in the generic sense).
The Portable Computer
From Wikipedia: "A portable computer is a computer designed to be easily moved from one place to another and included a display and keyboard together, with a single plug, much like later desktop computers called all-in-ones (AIO), that integrate the system's internal components into the same case as the display. The first commercially sold portable was the 50-pound (23 kg) IBM 5100, introduced 1975. The next major portables were Osborne's 24-pound (11 kg) CP/M-based Osborne 1 (1981) and Compaq's 28-pound (13 kg), advertised as 100% IBM PC compatible Compaq Portable (1983). These "luggable" computers lacked the next technological development, not requiring an external power source; that feature was introduced by the laptop. Laptops were followed by lighter models, so that in the 2000s mobile devices and by 2007 smartphones made the term almost meaningless. The 2010s introduced wearable computers such as smartwatches."
I was in college studying computer science in the mid-1980s and the IBM PC was the most available, but the Osborne and IBM luggable "portables" were there. They lacked a built-in battery for true portability.
The Pager -- Calling All Portable Computing Devices
"In the late
1980s and early 1990s, the pager (or beeper, as it was sometimes
called) was one of the earliest forms of portable communications device.
Each device was generally about the size of small wallet, with a
numerical screen (similar to the face of a calculator) on top. Each
pager had a phone number, which could be called if someone wanted to get
in contact with the owner. When a pager received a call, it 'beeped,'
hence its nickname." -- https://study.com/academy/lesson/the-evolution-of-portable-media-devices-cell-phone-technology.html
Laptop Computers
From Wikipedia: "A laptop, laptop computer, or notebook computer is a small, portable personal computer (PC) with a screen and alphanumeric keyboard. These typically have a clamshell form factor, typically having the screen mounted on the inside of the upper lid and the keyboard on the inside of the lower lid, although 2-in-1 PCs with a detachable keyboard are often marketed as laptops or as having a laptop mode. Laptops are folded shut for transportation, and thus are suitable for mobile use."
In the early-1980s I bought a
Tandy Radio Shack laptop computer with built-in battery, liquid-crystal
display, built-in phone modem, connection for a printer and tape backup
storage device. It was incredibly advanced for that moment in time. It wouldn't be until the 1990s that such a computer could really be done well and called a laptop. The Tandy laptop was an indicator of what was to come, and soon.
Batteries
As usual, the first ones weren't very good.
From Wikipedia: "In 1749, Benjamin Franklin, the U.S. polymath and founding father, first used the term "battery" to describe a set of linked capacitors he used for his experiments with electricity."
"Up to this point, all existing batteries would be permanently drained when all their chemical reactions were spent. In 1859, Gaston Planté invented the lead–acid battery, the first-ever battery that could be recharged by passing a reverse current through it."
"In 1899, a Swedish scientist named Waldemar Jungner invented the nickel–cadmium battery, a rechargeable battery that has nickel and cadmium electrodes in a potassium hydroxide solution; the first battery to use an alkaline electrolyte. It was commercialized in Sweden in 1910 and reached the United States in 1946"
"You
will be surprised to know that older laptops used to run on AA
batteries. Many AA batteries were required to run a laptop, and though
there were many AA batteries fitted in the laptop, they did not have a
long life. The number of AA cells also increased the weight of the
laptop. Running a laptop on AA batteries was quite an expensive
proposition, and the batteries needed to be changed frequently. The use
of AA batteries was also not good for the environment." --
https://sllapontamentos.blogspot.com/2011/07/history-and-origin-of-laptop-batteries.html
The 1990s gave us the Nickel Cadmium battery (NiCad) [ commercialized in the 1910 in Sweden ] and the Nickel Metal Hydride battery(NiMH)
"These batteries offered 2-3 times more capacity than NiCad batteries. There was no noticeable development in battery technology after the arrival of Nickel Metal Hydride batteries. The NiCad and the NiMH remained the preferred batteries in laptops manufactured the world over for a long time. These batteries can be even found today in older laptops. The improvement in the fuel cell technology paved the way for the invention of Lithium Ion batteries."
Lithium-Ion
Wikipedia: "Lithium is the metal with lowest density and with the greatest electro-chemical potential and energy-to-weight ratio. The low atomic weight and small size of its ions also speeds its diffusion, suggesting that it would make an ideal material for batteries. Experimentation with lithium batteries began in 1912 under G.N. Lewis, but commercial lithium batteries did not come to market until the 1970s"
The 1970s were a great innovative time for computers, software, the integrated circuit, and for batteries. But, the use of them didn't often appear until 10-20 years later.
For example, "... a research team managed by Akira Yoshino of Asahi Chemical, Japan, to build the first lithium-ion battery prototype in 1985, a rechargeable and more stable version of the lithium battery; Sony commercialized the lithium-ion battery in 1991."
The Japanese entered the international trade world and electronics and have been a huge force since that day.
Wikipedia: "In 1997, the lithium polymer battery was released by Sony and Asahi Kasei. ... such batteries can be specifically shaped to fit a particular device. This advantage has favored lithium polymer batteries in the design of portable electronic devices such as mobile phones and personal digital assistants, and of radio-controlled aircraft, as such batteries allow for a more flexible and compact design. They generally have a lower energy density than normal lithium-ion batteries.
In 2019, John B. Goodenough, M. Stanley Whittingham, and Akira Yoshino, were awarded the Nobel Prize in Chemistry, for their development of lithium-ion batteries."
The iPhone -- Truly Portable Personal Computing
"The iPhone is a line of smartphones designed and marketed by Apple Inc. that use Apple's iOS mobile operating system. The first-generation iPhone was announced by former Apple CEO Steve Jobs on January 9, 2007"
This was another major turning point, but still just another development in the microcomputer/integrated-circuit revolution begun in the 1970s.
EV Automobiles: from Des Moines to Tesla
"The first electric car in the United States was developed in 1890–91 by William Morrison of Des Moines, Iowa; the vehicle was a six-passenger wagon capable of reaching a speed of 23 kilometres per hour (14 mph)."
"To overcome the limited operating range of electric vehicles, and the lack of recharging infrastructure, an exchangeable battery service was first proposed as early as 1896."
"Most electric car makers stopped production at some point in the 1910s."
"In 1959, American Motors Corporation (AMC) and Sonotone Corporation announced a joint research effort to consider producing an electric car powered by a "self-charging" battery. AMC had a reputation for innovation in economical cars while Sonotone had technology for making sintered plate nickel-cadmium batteries that could be recharged rapidly and weighed less than traditional lead-acid versions."
"On 31 July 1971, an electric car received the unique distinction of becoming the first manned vehicle to drive on the Moon; that car was the Lunar Roving Vehicle, which was first deployed during the Apollo 15 mission. The "Moon buggy" was developed by Boeing and GM subsidiary Delco Electronics (co-founded by Kettering) featured a DC drive motor in each wheel, and a pair of 36-volt silver-zinc potassium hydroxide non-rechargeable batteries."
"The emergence of metal-oxide-semiconductor (MOS) technology led to the development of modern electric road vehicles. The MOSFET (MOS field-effect transistor, or MOS transistor), invented by Mohamed M. Atalla and Dawon Kahng at Bell Labs in 1959, led to the development of the power MOSFET by Hitachi in 1969, and the single-chip microprocessor by Federico Faggin, Marcian Hoff, Masatoshi Shima and Stanley Mazor at Intel in 1971. The power MOSFET and the microcontroller, a type of single-chip microprocessor, led to significant advances in electric vehicle technology. MOSFET power converters allowed operation at much higher switching frequencies, made it easier to drive, reduced power losses, and significantly reduced prices, while single-chip microcontrollers could manage all aspects of the drive control and had the capacity for battery management.
Another important technology that enabled modern highway-capable electric cars is the lithium-ion battery. It was invented by John Goodenough, Rachid Yazami and Akira Yoshino in the 1980s, and commercialized by Sony and Asahi Kasei in 1991. The lithium-ion battery was responsible for the development of electric vehicles capable of long-distance travel.
California electric car maker Tesla Motors began development in 2004 on the Tesla Roadster, which was first delivered to customers in 2008. The Roadster was the first highway legal serial production all-electric car to use lithium-ion battery cells, and the first production all-electric car to travel more than 320 km (200 miles) per charge"
The process of developing batteries and the first electric car in 1890 has today produced the Tesla automobile in 2004 -- 114 years.
The improvement of the EV engine and batteries continues. What about grid-scale or other kinds of battery storage meant for homes and businesses? There have been many ideas and some early efforts with "flow batteries" using a variety of chemicals and metals and processes. These mostly resemble the early days of all these technologies. There are some brilliant minds developing ideas which will remain for a very long time, but there are few breakthrough technologies.
The most amusing use of potential energy is the gravitational flow battery, but photovoltaics (PV) and ReDox Flow Batteries (RFB) interest me most. The PVs can help collect energy and convert it to electricity more directly than the steam turbine or the Internal Combustion Engine. The RFB with organic materials is much more durable than most other batteries and when they are built with organic materials they can be drained 100% without losing charging capacity or length of lifetime.
Photovoltaics
Like the early (and little used) discoveries about steam and burning a fuel there were early (and little used) discoveries about light energy. Here are a few from Wikipedia:
1839 - Edmond Becquerel observes the photovoltaic effect via an electrode in a conductive solution exposed to light.
1883 - Charles Fritts develops a solar cell using selenium on a thin layer of gold to form a device giving less than 1% efficiency.
1887 - Heinrich Hertz investigates ultraviolet light photo-conductivity and discovers the photoelectric effect
1904 - Wilhelm Hallwachs makes a semiconductor-junction solar cell (copper and copper oxide).
1921 - Einstein awarded the Nobel Prize in Physics for his work on the photoelectric effect.
1950s - Bell Labs produce solar cells for space activities.
1954 - On April 25, 1954, Bell Labs announces the invention of the first practical silicon solar cell. Shortly afterwards, they are shown at the National Academy of Science Meeting. These cells have about 6% efficiency. The New York Times forecasts that solar cells will eventually lead to a source of "limitless energy of the sun."
1960 - Hoffman Electronics creates a 14% efficient solar cell.
1976 - David Carlson and Christopher Wronski of RCA Laboratories create first amorphous silicon PV cells, which have an efficiency of 2.4%.
1980 - The Institute of Energy Conversion at University of Delaware develops the first thin film solar cell exceeding 10% efficiency using Cu2S/CdS technology.
2019 – The world record for solar cell efficiency at 47.1% was achieved by using multi-junction concentrator solar cells, developed at National Renewable Energy Laboratory, Golden, Colorado, USA.
Most solar panels today are far lower efficiency than the world record.
From Wikipedia: "Solar cell energy conversion efficiencies for commercially available multicrystalline Si solar cells are around 14–19%. The highest efficiency cells have not always been the most economical – for example a 30% efficient multijunction cell based on exotic materials such as gallium arsenide or indium selenide produced at low volume might well cost one hundred times as much as an 8% efficient amorphous silicon cell in mass production, while delivering only about four times the output.
However, there is a way to "boost" solar power. By increasing the light intensity, typically photo-generated carriers are increased, increasing efficiency by up to 15%. These so-called "concentrator systems" have only begun to become cost-competitive as a result of the development of high efficiency GaAs cells. The increase in intensity is typically accomplished by using concentrating optics. A typical concentrator system may use a light intensity 6–400 times the sun, and increase the efficiency of a one sun GaAs cell from 31% at AM 1.5 to 35%."
There are so many numbers and details mentioned in every article I read that I'm convinced there is still a lot of improvement to be found in the PV area. If it can reach 30% or more, then it easily beats petroleum-based fuel systems and the internal-combustion engine. The source is the sun and transportation of fuel isn't necessary, though the electricity may be transported some distance at the cost of a few percentage points of loss to heat.
Recent Developments
Links to interesting battery technologies:
Gravity Power: Utility-Scale Electricity Storage Systems
Organic Redox Flow Batteries - The true path to grid scale energy storage? - YouTube
ESS Inc. | Long-duration Energy Storage
ESS_OnePager_FINAL_5-10-21_lowres.pdf
Solar Thermal Energy
It should not be overlooked that solar thermal energy for heat can also be collected at a very low cost (more than for most any other system), if heat is what you want more than electricity. But, converting heat to electricity isn't an efficient process (only about 5% efficient).
Renewable Energy: Solar Air Heater - YouTube
How to Make Solar Water Heater 100°C Using Parabolic Trough - YouTube
How to Build a Solar Heat Collector - YouTube
Conservation at Home
And there are many advanced ways to build houses and other structures to avoid energy loss.
Passive House = 90% Home Energy Reduction! - YouTube
