Two frequent measures of power are British thermal units (Btu) and joules. All forms of vitality will be expressed in these models. One Btu is the amount of vitality needed to raise the temperature of one pound of water from 39 to forty degrees Fahrenheit. One joule is the quantity of power needed to elevate one hundred grams (3.5 ounces) upward by one meter (three.Three ft) whereas on the surface of the earth.
* As a consequence of the first Legislation of Thermodynamics, vitality and matter cannot be created or destroyed; they will only be remodeled from one form into one other.   
* As a consequence of the Second Regulation of Thermodynamics, when power is reworked from one type to another, some of it disperses, thus making it less helpful for performing work.[Eleven]   
Sensible Makes use of
* People have learned to harness vitality to perform duties corresponding to transporting people and merchandise, heating and cooling homes, farming, cooking, manufacturing goods, speaking across vast distances, and producing gentle.
* The average annual energy consumption within the U.S. is 309,000,000 Btu per person. To generate this amount of energy via physical human effort (like pedaling bicycles to drive generators) would require 208 individuals working nonstop for a year.
* “Embodied energyrefers back to the vitality utilized in making supplies. For example, to make a typical clay brick weighing 5 pounds requires about 5,386 Btu of energy. The supplies of a typical home embody about 850 million Btu, which is equal to the power that could be generated by 573 folks pedaling bicycles nonstop for a yr.
* In 2013, energy expenditures within the U.S. have been 8.3% of gross home product (GDP), or $1.4 trillion ($1,383,045,600,000). In inflation-adjusted 2015 dollars, this amounts to $4,446 for each U.S. resident or $11,491 per household. 
* The prices of most products are affected by the costs of vitality, even products with low embodied energies because the costs of power affect the costs of transporting products. As a result of power prices affect the costs of merchandise, greater vitality prices are inclined to drive up unemployment, drive down wages, and cause other unfavorable economic effects. Such penalties are usually harsher in poorer nations.  
* Roughly one third of the world’s inhabitants doesn’t have access to trendy types of energy. In these areas, folks use biomass (primarily wood) for about 80% of their vitality, and women and kids spend a median of 9-12 hours a week amassing firewood. Per the Institute for Plasma Physics in the Netherlands:
* Higher energy costs drive up the costs of food. This has larger impacts on poorer nations and people as a result of they spend a bigger portion of their earnings on meals.  In Haiti throughout 2007 and 2008, increased vitality prices contributed to increased meals prices, driving Haiti’s poorer people to obtain nourishment from cookies fabricated from mud.
* Per the Congressional Research Service, “The financial properly-being and financial security of the nation relies on having stable energy sources.”
* Per the U.S. Government Accountability Office, “Americanseach day lives, as properly because the economic productivity of the United States, rely on the availability of energy”
* Per the textbook Introduction to Air Pollution Science, “The availability of inexpensive electric energy is essential for public well being and economic prosperity.”
– “Liquid fuels play an important function within the U.S. energy system and financial system, and access to inexpensive liquid fuels has contributed to the nation’s economic prosperity.br> – “Cheaper vitality permits the economy to broaden furtherbr> – “increasing vitality manufacturing has speedy benefits for the economy.” 
* Per the textbook Microeconomics for At the moment, countries with slower economic progress “are much less in a position to satisfy primary needs for food, shelter, clothing, schooling, and well being.”
U.S. Power Supplies
* During 2016:
– petroleum equipped 36.9% of all primary power consumed in the U.S.
– pure fuel provided 29.2%.
– coal supplied 14.6%.
– nuclear equipped 8.6%.
– hydroelectric provided 2.5%.
– biofuels supplied 2.Three%.
– wood supplied 2.2%.
– wind supplied 2.0%.
– solar provided zero.6%.
– biowaste provided zero.5%.
– geothermal equipped 0.2%.
* The following graphs present the components of U.S. energy consumption over time. The primary graph reveals consumption measured in BTUs. The remaining present consumption measured as a portion of whole U.S. vitality consumption. Each succeeding graph makes use of a smaller scale to offer increasing decision.
[Forty]  [forty two]
* Knowledge from the graphs above:
Components of U.S. Vitality Consumption
Sectors & Electricity
* The U.S. Energy Data Administration (EIA) divides the energy market into 4 main sectors: residential, industrial,[forty eight] transportation,[forty nine] and industrial. 
* In 2014, the residential sector consumed 22% of all U.S. power, the commercial sector consumed 18%, the transportation sector consumed 28%, and the industrial sector consumed 32%.[Fifty two]
* EIA sometimes classifies “electric poweras a separate sector, although the electricity produced by this sector is consumed by the 4 main sectors.
* In 2014, the electric energy sector consumed 39% of all U.S. power.
* Per the Institute for Plasma Physics in the Netherlands:
– “Electricity is the most versatile form of power: it can be utilized for just about any software.br> – Using electricity to generate heat “is normally a lot dearer than utilizing fossil fuels, and it’s only used for comparatively small amounts of heat.br> – “Electricity can also be quite laborious to store in massive quantities. You need large, heavy batteries to store an inexpensive amount of electrical power.br> – “The central technology of electricity means it needs to be distributed over the nation in order to deliver it to your home. This causes a median loss of energy of 10%, and desires a large and costly distribution system.”[fifty six]
* During 2015:
– coal generated 33.2% of all electricity produced within the U.S.
– pure fuel generated 32.7%.
– nuclear generated 19.5%.
– hydroelectric generated 6.0%.
– wind generated 4.7%.
– wooden generated 1.0%.
– photo voltaic generated 0.9%.
– petroleum generated 0.7%.
– biomass (apart from wooden) generated 0.5%.
– geothermal generated zero.Four%.
* Financial development is a key consider the growth of electricity technology.[Fifty nine]
* The next graphs show the parts of U.S. electricity technology over time. The primary graph shows era measured in kilowatt hours. The remainder present era measured as a portion of total U.S. electricity era. Every succeeding graph uses a smaller scale to offer increasing decision.
* Not including power sources that aren’t purchased or sold (like self-procured firewood), during 2014:
– petroleum and different liquid fuels provided 33% of all energy consumed on the earth.
– coal provided 27%.
– pure fuel provided 23%.
– hydroelectric and different renewables equipped 12%.
– nuclear supplied four%.[Sixty three] 
[sixty five] 
* During 2014:
– coal generated forty% of all electricity produced on this planet.
– pure gasoline generated 22%.
– hydroelectric generated 17%.
– nuclear generated eleven%.
– petroleum and other liquid fuels generated four%.
– wind generated 3%.
– different renewables (resembling wood) generated 2%.
– photo voltaic generated zero.9%.
– geothermal generated zero.Three%. [sixty eight]
* When modern vitality is unavailable or expensive, individuals are inclined to burn more wood, crop waste, manure, and coal in open fires and easy house stoves. Open fires and home stoves do not burn fuel as efficiently as business energy technologies, and hence, they produce elevated levels of outside and indoor pollutants. The added consumption of wood additionally causes deforestation. [seventy two] [seventy three]  [seventy five]
* Assessing the full environmental impacts of various energy applied sciences requires wanting past the consequences at a single point of manufacturing, use, or disposal. To do this, researchers perform “life cycle assessmentsor LCAs. Per the U.S. Environmental Safety Agency (EPA), LCAs enable for:
* Per a 2008 paper in Environmental Science & Expertise:
* The air pollutants generated by vitality sources range with factors resembling combustion strategies, manufacturing techniques, and pollution management applied sciences.[Seventy nine] [eighty] For example, bituminous coal combusted in a fluidized bed boiler without pollution controls produces one tenth the sulfur dioxide of the identical fuel burned in a cyclone boiler with out pollution controls.[Eighty one] [eighty two] 
– electricity generated by nuclear, hydropower, solar, geothermal, and wind energy emits a fraction of the air pollutants of fossil fuels.    
– geothermal heat pumps generate much less pollutants than another know-how for heating and cooling.
– biofuels normally emit much less air pollutants than petroleum-primarily based fuels, although some biofuels emit more nitrogen oxides and risky natural compounds over their lifecycles.  [ninety two] [ninety three] [ninety four]
– natural fuel combustion generates the bottom air pollutant emissions of all fossil fuels.[Ninety five]    
– as of 2000, electricity generated by coal combustion created extra sulfur dioxide and nitrogen oxides than some other gas.
* Per the U.S. Department of Energy (2010):
* Within the U.S. from 1990 by 2015, sulfur dioxide (SO2) emissions per Btu of coal-generated vitality decreased by 86%, and nitrogen oxides (NOx) emissions decreased by 78%.
* For the reason that late 1970s, new automobiles have been equipped with catalytic converters, an “anti-pollution devicethat converts “exhaust pollutants to regular atmospheric gases equivalent to nitrogen, carbon dioxide, and water.”  
* Facts about air pollution levels and their effects are detailed in Simply Factsresearch on pollution.
* Carbon dioxide (CO2) contributes extra to the greenhouse effect than another gasoline released by human exercise. 
– electricity generated by nuclear, photo voltaic, geothermal, and wind energy emits a fraction of the greenhouse gases of fossil fuels. [a hundred and ten]   
– hydropower’s “air emissions are negligible as a result of no fuels are burned. Nevertheless, if a considerable amount of vegetation is rising alongside the riverbed when a dam is constructed, it will possibly decay in the lake that is created, causing the buildup and launch of methane, a potent greenhouse gas.”
– when extracting natural gas, coal, and petroleum from the bottom, uncombusted methane might be launched. Methane is a greenhouse gasoline that’s 28 instances extra potent (per unit mass) than CO2.[One hundred fifteen]  
– When combusted, fossil fuels emit the next amounts of CO2:
Pounds of CO2 per million Btu
Diesel gas & heating oil
* Biofuels comparable to ethanol generate CO2 when burned, however the crops used to make these fuels absorb an equal amount of CO2 as they grow. Nevertheless, planting, fertilizing, harvesting, processing, and distributing ethanol emits extra CO2 than extracting, refining, and distributing gasoline.    
* Per the U.S. Congressional Finances Workplace (CBO), lifecycle analyses comparing CO2 emissions of corn-based mostly ethanol and gasoline have produced various results, but probably the most authoritative examine in the eyes of the federal government (performed by Argonne National Laboratory) estimates that, on average, corn-based ethanol produces about 20% less CO2 than gasoline.
* Another sort of biofuel called cellulosic ethanol has the potential to supply 60-ninety five% much less CO2 emissions than gasoline. This fuel is more difficult to manufacture than regular ethanol, and as of 2016, producers have been unable to make enough of it to fulfill the mandated amounts specified in federal legislation.      
* Converting undeveloped land to domesticate crops for biofuels creates CO2 emissions as a result of current plant life is eliminated and the soil is disrupted. If this land is repeatedly used to provide biofuels, the net CO2 emissions shall be lower than using fossil fuels. The timeframe till this breakeven point happens relies upon upon factors such as the type of land converted and sort of biofuel produced. Per a 2008 paper within the journal Science, the CO2 breakeven time of changing:
– wetter parts of Brazil’s woodland/savanna region to produce sugarcane ethanol is about 17 years.
– dryer portions of Brazil’s woodland/savanna area to produce soy biodiesel is about 37 years.
– central grasslands of the U.S. to produce corn ethanol is about ninety three years.
– lowland tropical rainforest of Indonesia and Malaysia to provide palm biodiesel is about 320 years.
– Amazonian rainforest to supply soy biodiesel is about 320 years.
– tropical peatland rainforest to produce palm biodiesel is about 840 years.
* Per the U.S. Energy Information Administration:
* Details about greenhouse gases and local weather change are detailed in Simply Factsresearch on international warming.
* As a way to carry out useful work, power usually should be transformed from one form to a different. Most power on earth ultimately comes from the solar, and this power sometimes undergoes multiple conversions earlier than it is used to accomplish a selected task. For instance, the power that ultimately powers a gentle bulb may have the following history:
– The means of fusion converts the nuclear vitality of elements within the sun into sunlight (electromagnetic energy).
– When sunlight strikes the earth’s oceans, a few of it is transformed to thermal vitality.
– This thermal power heats the water and causes it to evaporate and rise, thus changing a few of it to gravitational vitality.
– When this water falls as rain, it fills rivers that drive the turbines of hydroelectric dams, thus converting a few of it to mechanical energy.
– This mechanical power is used to show generators, thus converting some of it to electrical vitality.
– When this electrical power flows by way of gentle bulbs, a few of it is transformed back to electromagnetic vitality (gentle). 
* With every conversion process, some quantity of the power is dispersed, thus making it less useful for performing work. Per the U.S. Nationwide Academy of Sciences:
* In the U.S. from 1949 to 2015, energy consumption per inflation-adjusted dollar of financial output decreased by 63%:
* Homes built in the U.S. from 2000-2009 are about 30% larger than properties built previous to this period, however they use about 2% extra complete energy. This result is primarily due to raised insulation and elevated efficiencies of heating and air conditioning technologies.
* Properties constructed within the U.S. from 2000-2009 use about 18% more energy on appliances, electronics, and lighting than older properties. This is because newer properties usually tend to have “dishwashers, clothes washers, clothes dryers, and two or more refrigerators.Also, as a result of they’ve extra square footage, newer houses are inclined to have extra “computers, TVs, and Tv peripherals reminiscent of digital video recorders (DVRs) and video sport systems.”
* Growing the effectivity of electronics, appliances, and lighting scale back the demand for vitality and can save consumers money if the added price of creating these products extra environment friendly doesn’t exceed the cost of the power saved. 
* Vitality Star is a joint program of the U.S. Environmental Safety Company and Division of Energy. Per the program’s web site:
* In 2010, the U.S. Authorities Accountability Workplace (GAO) printed an investigation of Power Star by which GAO submitted 20 “bogus productsfor approval. Fifteen of the products had been accredited, 2 were rejected, and 3 were unanswered on the time the report was published. Among the merchandise certified as Energy Star compliant have been:
– a gasoline-powered alarm clock.
– a geothermal heat pump eligible for federal tax credits and state rebate packages that purportedly had higher efficiency than any Vitality Star product.
– a computer monitor that was accredited within half-hour of submission.
– “a room cleaner represented by a photograph of a feather duster adhered to an area heateron a pretend manufacturer’s net site.
* The U.S. Green Constructing Council, per its webpage, is a “nonprofit group committed to a affluent and sustainable future for our nation by way of value-efficient and vitality-saving inexperienced buildings.” This group supplies numerous kinds of inexperienced building certifications that qualify the homeowners for government incentives, equivalent to tax breaks and zoning allowances. This score system is named LEED for “Leadership in Vitality and Environmental Design.”
* In 2012, USA Right this moment carried out an investigation of colleges with green constructing certifications (resembling LEED) and found:
– “More than 200 states, federal businesses and municipalities require LEED certification for public buildings.br> – out of 239 faculties within the Houston (Texas) Independent Faculty District, three newly built “green schoolsranked 46th, 155th, and 239th for power costs per scholar.
– “Building a LEED-certified faculty often provides 2% to three% to building prices, and as a lot as 10% within the case of a Selinsgrove, Pa., high schoolbr> – a Inexperienced Building Council brochure had claimed that “green schools save moneyprimarily based upon pre-development cost estimates of 30 colleges. One of these faculties, situated in Olympia, Washington, was projected to make use of 28% less power than standard schools. In itsfirst two years of operations, the college used 19% more vitality than typical colleges.
– a Inexperienced Constructing Council brochure had claimed that “green faculties help improve pupil efficiency,but a USA As we speak “review of student check scores for sixty five faculties in eleven states that have been rebuilt to get LEED certification and have been open for no less than two yearsfound “no clear patternof improved student efficiency.[A hundred and fifty]
* Per the U.S. National Academy of Sciences:
Prices of Transportation Fuels
* Transportation fuels have completely different energy densities, and thus, the worth per quantity of every fuel doesn’t precisely replicate the power supplied to consumers. For instance, the power content of a gallon of ethanol is 31% less than a gallon of gasoline. Hence, a car fueled with E85 (a mixture of 70-eighty five% ethanol and 15-30% gasoline) will get 25-30% much less miles per gallon than the identical automobile when it’s fueled with pure gasoline.    
* Like ethanol, the volume of biodiesel blended with regular diesel is shown by a quantity that follows the primary letter of the named gas. Thus, B20 accommodates 20% biodiesel and 80% common diesel.
* On an energy-equivalent basis, the typical subsidized retail prices (together with taxes) for transportation fuels throughout 2016 have been as follows:
Nationwide Average Price in
* A federal regulation recognized because the “Renewable Gas Standardrequires U.S. shoppers to make use of certain quantities of ethanol and other biofuels. This mandate makes use of a compliance mechanism that transfers a few of the costs of producing these fuels from biofuel firms to petroleum corporations. These added prices are then passed on to customers within the type of upper gasoline costs.   
* During 2016, a federal tax credit subsidized biodiesel at a price of $1.00 per gallon.
* Federal payments, tax breaks, loans, and loan ensures subsidize petroleum and pure gas manufacturing at a fee of about $0.01 per gasoline-gallon equal.
* Combining the information above yields the following common prices for transportation fuels throughout 2016 without federal subsidies:
Unsubsidized Value in
Relative to Gasoline
Compressed Natural Gas
Prices of Electricity
* From 1929 to 1967, the inflation-adjusted average price of electricity for U.S. residential clients declined from about 60 cents per kilowatt hour to 10 cents, and it stayed roughly around this figure by 2012.
* The inflation-adjusted common costs of electricity since 2004 for all U.S. customers and the 4 main vitality sectors are proven within the graph under:
* Demand for electricity varies on an hourly, daily, and seasonal basis on account of components resembling:
– the time of the day, which influences the usage of lighting, computers, and different electric units.
– the weather, which influences the usage of heating, air conditioning, and ventilation methods.  
* As proven in the following graph, the terms “baseloadand “peak loadare used to describe the minimal and maximum demands for electricity over a given time interval. The term “intermediate loadis used to describe the range between them. 
* Coal is the dominant energy supply for producing baseload capability, as a result of low gas prices make coal plants inexpensive to run constantly, which is right for generating baseload capability. For the same purpose, nuclear energy is a major supply of baseload capability. Natural gasoline, hydropower, geothermal, and waste-to-energy plants are additionally sources of baseload capability.   
* Natural gasoline is the dominant power supply for generating intermediate and peak load capacity as a result of natural gas power plants can ramp up and down quickly, which is ideal for intermediate and peak load capacity.   
* In 2009, pure fuel grew to become competitive with coal for producing baseload capability in some areas of the U.S. This was primarily on account of increased domestic pure gas manufacturing, which diminished costs. Other components included elevated coal costs, stricter environmental rules, and enlargement of pure gas pipelines.   
* In 2012, both coal and pure gas fuels had been aggressive for generating baseload capability underneath differing circumstances in different areas of the U.S.
* For existing energy plants, natural gasoline plants that make use of a excessive efficiency technology referred to as “combined cyclecan generate baseload power less expensively than coal plants when pure gas is about 1.5 occasions the worth of coal.   In 2015, the typical power-equivalent value paid by electric power plants for natural gas was about 1.5 times the worth of coal.
* Per the U.S. Vitality Info Administration (EIA), electric utilities and authorities entities that regulate them:
* Figuring out which electricity-producing technologies will provide the bottom value whereas maintaining reliability is complicated by the next components:
– Energy plants are capital-intensive and have lifespans measured in many years. As a result of these are lengthy-term investments, there’s ample time for market situations and authorities energy polices to alter, and this creates risk.     
– Utilities should produce sufficient electricity to satisfy their customersdemands on a second-by-second basis, and the costs of producing this electricity differ depending upon when it’s produced. During intervals of high demand, electricity is costlier to generate. Thus, applied sciences that generate electricity on demand have more worth to utilities than intermittent sources, similar to wind and solar.      
– Choices to spend money on new generating capability frequently contain elements which are distinctive to each utility and every point in time.
* A commonly cited measure of the costs of constructing and operating new energy plants is the “levelized costknowledge revealed by EIA. Levelized prices reflect “both the capital and working costs of deploying and running new utility-scale technology capability of any given kind.”  Per EIA:
* The next features, caveats, and limitations are inherent in EIA’s levelized costs:
– They remove the effects of authorities subsidies.
– They account for the costs of buying or leasing land to function the technology services.
– They don’t take away the consequences of taxes or authorities regulations. 
– They don’t measure precise prices however are projections of future prices.
– They range with EIA’s assumptions: – In 2011, EIA lowered the projected 2016 levelized cost for wind by 35% beneath its projection from one year earlier.
– In the identical projections, EIA lowered the price for photovoltaic (PV) photo voltaic by forty seven%.
– In 2015, EIA reduced the projected 2020 levelized capital value for geothermal by 57% beneath its estimate from two years earlier. 
– The vast majority of nuclear power plants have been licensed to function for 60 years.
– Per a 2008 Congressional Budget Office report, “numerous power stations inbuilt the primary half of the earlier century are still in use.” 
– Per a 2013 report commissioned by EIA, solar panels have an expected life of 20-30 years.
* In 2015, EIA projected the next levelized prices for plants that start producing electricity in 2020:
Plant sort (lowest cost option from every major class)
Price Enhance Relative to Pure Gas
Natural Gasoline Advanced Combined Cycle
Non-Dispatchable Applied sciences
PV Photo voltaic
* Per EIA, “a better assessment of economic competitiveness might be gained through consideration of prevented cost, a measure of what it could value the grid to generate the electricity that’s otherwise displaced by a brand new era undertaking, as well as its levelized cost.Calculating these costs involves a better diploma of complication than levelized costs. 
* In July 2013, EIA printed a preliminary discussion paper utilizing prevented prices and levelized costs to compare the projected 2018 and 2035 values of advanced combined cycle pure gas (Adv CC), onshore wind, and PV photo voltaic with different subsidies given to wind and photo voltaic. Because there is important variability in factors that affect electricity prices and values in several areas of the country, the paper contained assessments of twenty-two regions within the U.S. electricity system. It found that with out subsidies for wind and with a 10% investment tax credit score for photo voltaic:
– In 2018, the projected economic value of the wind and solar programs is “negative and considerably belowpure fuel advanced mixed cycle tasks “in all regions.br> – By 2035, the financial value of onshore wind is positive in 6 of 20 regions the place the technology will be built, and in three of 21 areas for photo voltaic PV (with 5 additional regions near breakeven).br> – “Direct comparison of LCOE values considerably understate the benefit of Adv CC relative to onshore wind in terms of financial worth in all regions, whereas overstating the advantage of Adv CC relative to solar PVbr> – “Solar LCOE remains considerably greater than wind LCOE throughout the projection period”
* The next features, caveats, and limitations are inherent on this evaluation:
– It is based on projections of adjusting future financial circumstances, akin to rising natural gas costs beginning round 2025. 
– It does not present an evaluation of photo voltaic with out the effect of authorities subsidies.
– It doesn’t take away the consequences of existing taxes or