History of Energy and Energy Efficiency

History:

Prior to the 19^th century, nearly all, and prior to the 20^th century, much of the energy used (ie, converted) by humankind was renewable energy:

1.      Human and animal muscle.  The conversion steps are solar à biomass (chemical energy) à muscle (ie, bio-mechanical energy) à work.  “Animals have been used for traction since the beginnings of agriculture some 10,000 to 12,000 years ago.”

2.      Wind for sailing: solar à kinetic energy of wind à kinetic energy of ship.  “Wind has been used to power ships in the Mediterranean for between 5,000 and 6,000 years.”

3.      Wood for cooking, heating, lighting, and working materials: solar energy à biomass (chemical energy) à thermal energy and light.  “For perhaps 500,000 years, people have used wood….”

4.      Water (ie, hydro-power) and wind for operating mills mainly for the grinding of grain and the sawing of wood: potential (and kinetic) energy of water and kinetic energy of wind à kinetic and mechanical energy of the mill (ultimately dissipated as heat, ie, converted into heat by friction).  “Mills powered by wind and water were used 2,000 to 3,000 years ago..”

“Natural forces have been used for many centuries to move objects for transport and production.”

Colonial (17^th and 18^th century) America:

Because of the need to move goods and people by sailing ships, major cities were located near the coast and major river estuaries.  However, manufacturing required falling water.  Thus, the mills tended to be located upstream of the major cities.

The industrial revolution, starting in the later part of the 18^th century, changed things.  In England, coal became an important fuel for smelting and casting iron and for converting water into steam and operating steam engines.  Previously, coal had been used for heating and forging.  The mining of coal, the making of iron, and the use of steam engines for transport reinforced one another, and fed industrialization.  Of course, wood also was used as the source of heat for iron working and steam engines.  In America, wood remained predominate until the later part of the 19^th century (out-living the importance of wood in England).  Also, wood made a better charcoal for forges than coal.  However, by the end of the 19^th century, coal was king in both America and England.

Steam and steam engines had significant impacts on society.  Means of transport changed.  Land-based transport by railroad became very significant, and manufacturing was no longer dependent on falling water, meaning manufacturing could be concentrated in the cities.  Steam engines drove belts, which drove machines throughout the manufacturing plants.  However, muscle power remained significant, especially on the farm and in the rural regions, and even in the manufacturing sector.  This was the situation existing at the turn of century from the 19^th to 20^th century.  Although oil was “discovered” in the middle of the 19^th century, and the internal combustion (IC) piston engine was invented about the same time, oil and IC piston engines remained “emerging” in the 19^th century.  Central electricity generation emerged in the latter part of the 19^th century, and grid electricity became available in the larger cities during this period.  However, some rural sectors remained without grid electricity until the 1930s.  [If rural electrification had arrived later, innovation and development of wind turbine electricity generating systems would have occurred in middle part of the 20^th century – instead wind turbine technology “fell on hard times” until the energy crises of the 1970s.]

In the first quarter of the 20^th century major changes occurred.  The electric motor became an integral part of the manufacturing sector.  Now, individual work stations (of course, not computer work stations) could have their own motors.  Long, cumbersome, dangerous belts from the central steam engine were no longer required in the manufacturing plant.  This transformed manufacturing, giving much improved flexibility and efficiency.  At first, companies generated their own electricity at the plant site, but as the 20^th century evolved, companies switched to purchasing electricity from the grid, produced by the utility.  The other major change was the IC piston engine.  By the 1920s this emerged as a major player in the transportation sector.  Automobiles became the preferred mode of personal transport.  Electric trolleys died off in many cities.  By the middle of the 20^th century, oil replaced coal as the predominant fossil fuel.  The 1940s saw the last (or nearly the last) steam-driven train.  The replacement (at least in the USA) was the diesel-electric train.

During the 1950s and 1960s energy use rapidly grew in the USA.  Oil use grew significantly as did the use of natural gas, though natural gas entered the scene later than oil.  [In Europe, natural gas did not become significant until the 1970s.  In fact, coal gas (aka town’s gas), a synthetic mixture of hydrogen, carbon monoxide, and light hydrocarbons such as methane, continued to be used in some places well after WWII.]  By the 1960s there was concern energy use was outrunning domestic energy production.  King Hubbert, famous for the Hubbert curves, predicted oil production in the USA would peak in about 1970.  (See reference on page 38 of Boyle.)  Hubbert “hit it on the head.”  By 1970 we were significantly importing oil.  By 1973, when the first major oil crisis hit, induced by war between Israel and Arab nations, the USA was importing about 40% of its oil.  But even before the 1973 crisis, as noted above, there was significant concern about the domestic supply of oil in the USA.  In 1973, some European nations were importing higher fractions of their oil than the USA.  Natural gas use peaked in the USA in the early 1970s – this was domestically produced.  [Only now is natural gas use returning to the levels of the early 1970s – with the help from imports from Canada.]  The only fossil fuel to reach a minimum in use in the 1950-1960 period was coal.  Nuclear energy as a means of generating electricity came on the scene in the 1960s.  At first it was envisioned nuclear energy would help solve our dependency on foreign sources of energy.  After all, it was claimed in the 1950s that electricity from nuclear power plants would be “too cheap to meter”.  During the 1960s and early 1970s many nuclear power plants were ordered by the utilities in the USA.  However, by the mid 1970s it became clear to many in the energy business that nuclear energy was not cheap.  This was a major factor in the canceling of about one half of the orders for nuclear power-plants.  In fact, of the approximately 100 nuclear-electric generating stations operating in the USA today, producing about 20% of the nation’s electricity, nearly all were ordered over the 1965-1973 period.  However, construction of some of the plants was not completed until about 1990. 

What was the response to the 1973 oil crisis?  The economy slowed, resulting in less demand for energy.  People bought smaller automobiles – a key opening for the Japanese auto-makers.  People couldn’t “give away” big cars.  The use of coal for generating electricity was strongly revived.  Significant taxpayer money was invested in coal burning research and development (there had been little R&D on coal burning since the 1920s).  The few nuclear power-plants that came on line in the 1970s helped with respect to electricity.  Major strides were made in energy efficiency and conservation – government and utilities put incentives into place to encourage conservation and the use of efficient appliances and equipment.  Significant changes were put into place regarding the use of energy by the built environment.  The highway speed limit was reduced to 55 mph, in order to improve economy in gasoline use.  During the 1970s significant R&D was started and accomplished on clean combustion, since air pollution had become a nasty problem in many cities as energy use exploded in the 1950 and 1960s.  The USEPA was established about 1970.  Significant R&D was initiated in the 1970s on solar energy.  The Solar Energy Research Institute, Golden, Colorado, was established by the federal government.  The government funded and encouraged significant work on solar energy.  However, little of this technology developed quickly enough to be of practical benefit in the 1970s.  Thus, when a conservative administrated entered the White House in 1981, solar energy R&D funded by the federal government was greatly reduced. 

The second oil crisis hit in 1979.  Like the first crisis six years earlier, this crisis was induced by difficulties in the middle East – this time the hostage-taking in Iran.  Gasoline lines again formed in USA – in the summer of 1979.

Over the 1973 to 1983 period, energy use in the USA decreased by 3% and oil use decreased by 14%, though interestingly, the peak in oil consumption occurred in 1978, and is just now returning to that level.  Over the 1970-1980 period, the efficiency of automobiles approximately doubled because of the use of lighter and smaller vehicles with improved aerodynamics and because of the computerization of engines (ie, electronic fuel injection controlled by a computer on board).  The built environment became more energy efficient.

Over the 1973-1983 period, use of electricity grew, indicating the desirability of this form of energy and our dependency on it.

Many European nations, hit very hard by the oil crises of the 1970s, have maintained high taxes on engine petrol to discourage excessive use.  And they have maintained strong programs in energy conservation and efficiency, and they are aggressively moving forward on renewable energy through incentives, subsides, and funding of technology.  [In light of this, it should come as no surprise to you that the texts for this course are of European origin.]         

In the USA, during the period since 1983, energy use has increased, though not as rapidly as in the 1950s and 1960s.  Today we use about 40% more energy than in 1970 [though we domestically produce only 15% more energy than in 1970].   [However, as noted above, oil and natural gas consumption are just now returning to their early 1970s levels.]  We again drive gas-guzzlers, though we no longer call them cars.  Over the 1991-99 period, the average annual growth rate in energy use in the USA was 1.75%.  A nearly identical average annual growth rate holds for oil.  For comparison, the population growth rate was about 1.0% per year.  Electricity use, on the other hand, has grown at 2.3% per year on average for the 1991-99 period, and the average annual growth rate of the GDP was 3.6% of this period.  Our appetite for electricity continues to be strong – behavior that may well accelerate as we embrace and become ever more dependent on the micro-chip.  Information technology and electronic transfers might become the biggest uses of energy.

The Solar Energy Research Institute, now known as the National Renewable Energy Laboratory, has climbed back and developed new facilities – for example, a center for wind turbine evaluation near Boulder, Colorado.  Most important, since the early 1980s, in significant part through private enterprise, key renewable energy technologies have made significant improvements, gained a small but significant market share, and may be on the verge of substantial growth.  Examples are the wind turbine and the solar PV panel.

However, we must also recognize the USA and the world still mainly rely on fossil energy.  In the USA, coal use is growing in lock-step with electricity use.  Currently the USA imports 55% of its oil [because domestic oil production has fallen about 40% since 1970].   Renewable energy is only significantly represented by large-scale hydro-electric and by wood waste burning in the paper and forest products industry in the USA (and Europe) and by domestic burning of biomass for heating and cooking in the developing nations.

Efficiency:

Energy conversion efficiency is more efficient today than it was 100, 50, and 10 years ago.  For example, early in the 20^th century, the efficiency of central electricity generating stations was about 10%.  Now, the average for fossil and nuclear power-plants is about 33%.  And new types of power-plants are almost 60% efficient – these are the newest combined cycle combustion turbines – a combination of a gas turbine (as used in jet aircraft) and the steam turbine – usually they burn natural gas and currently they account for over half of the new electrical generating facilities being installed worldwide.      

Energy conversion efficiency is defined as: energy output (eg, electrical energy) divided by the energy input (eg, the chemical energy of the fuel burned).

The efficiency of the gasoline engine has steadily improved since its early development.  This has happened because of two factors: our ability to use higher compression ratios, which is controlled by our ability to burn gasoline without unwanted spontaneous explosions in the cylinder, and electronic control of engines.  However, the overall efficiency of gasoline engines used in automobiles, from the oil well to the automobile wheel, is only about 15%.

Gas furnaces for home heating are now 80 to 95% efficient, and heat pumps (used in the PNW) are 200 to 300% efficient.  In the case of the heat pump, the efficiency (called the coefficient of performance) is defined as the heat energy delivered to the space being heated divided by the electrical energy purchased to run the compressor of the heat pump.