Tag Archives: pollution

Mercury

Mercury in the Evironment

A human body contains on average 3 grams of Mercury (Hg), in the form of dental amalgam. Cremation releases the material to the atmosphere in the form of gaseous elemental Mercury. As Mercury is a well known toxin, should there be concern over its release to the environment via cremation?

Currently there are over a million cremations a year in the United States, resulting in the release of about three tons of Mercury. That is a lot of Mercury but it pales in comparison to the Mercury released from burning coal – over 50 tons per year.

Just how dangerous Mercury exposure is depends on two important variables, the chemical form and the amount of the exposure (dose). In the elemental form, for example the liquid in older thermometers, it has a relatively low acute toxicity. If inhaled in the gaseous form or absorbed through the skin in the liquid form it is poorly metabolized and rapidly excreted unchanged. We are all exposed to trace amounts of elemental mercury from airborne sources, but in this form it presents little hazard.

Even children on a playground near a crematorium are at little to no risk from this type of Mercury. This doesn’t mean that the Mercury from a crematorium is of no consequence, but the explanation is more complex.

Mercury in the form of a salt is much more toxic. Lewis Carroll’s Mad Hatter of Alice in Wonderland was a parody of the real life risk of hatters of the 19th century. Exposure to certain Mercury salts caused tremors and a form of dementia.

The Mad Hatter

The Mad Hatter

Hat makers in Central Asia used felt which was obtained by separating the fir from the skin of small animals. Traditionally camel urine was used to help form the felt. When felt preparation moved to Europe, hatters substituted their own urine. It was soon discovered that hatters who had syphilis and were being treated with Mercury salts made better felt! Thenceforth, solutions of Mercury salts were substituted for urine for hat making.

The most toxic form of Mercury comes in the form of certain organomercurials, specifically Methylmercury. In this form it is easily absorbed, where it binds to and destroys nervous tissue. This is the form of Mercury found in both fresh and saltwater fish.

Biomagnification

Biomagnification

The first recognition of the toxicity (principally nerve damage) of Methylmercury occurred in Japan in 1956 and was referred to eponymously as Minamata Disease. Chisso Chemical Company on Minamata Bay manufactured industrial chemicals and disposed of their wastes in the bay. A component of the waste was Methylmercury which was absorbed by fish and shellfish. Consumption of the sea food resulted in chronic poisoning and thousands of deaths.

This brings us back to the crematorium and the release of the relatively non-toxic elemental Mercury. When this mercury is deposited on soil or in water, it makes its way to the benthic layer – basically the mud at the bottom – of streams and lakes. There, anaerobic bacteria convert it to the much more toxic Methylmercury. It bioaccumulates in the smallest organisms, then up the food chain to fish.

The long and short of it is that it is not a good idea to allow release Mercury to the environment. The problem is easily solved however by simply removing the Mercury amalgam from teeth before cremation, as has been proposed by Humphrey Funeral Service. They are currently seeking a permit to construct a crematorium near Center Valley here in Pope County. If so they will be the first in the nation to take this simple but environmentally important step. Occam’s razor, don’t operate a crematorium without it.

As

Arsenic Anyone?

A popular talk show doctor recently had several brands of Apple juice tested and claimed to have found Arsenic. Whereas nobody wants poison in her food, the question of the amount and its relevance is important. First a little background on Arsenic.

One of the first things that come to mind in association with Arsenic is poison. And indeed it is poisonous. It has been used as a pesticide because it is generally poisonous to all forms of life, rats, cockroaches, even some fungi succumb to it. Ironically it is also known to be an essential trace element for some organisms and possibly humans in tiny, tiny amounts.
 
Arsenic has been known since antiquity and is poisonous to varying degrees depending on its form. As important as the potency of a poison is the amount of the poison. A seventeenth century physician-chemist by the name of Paracelsus famously proclaimed “everything is poisonous, nothing is poisonous, the dose makes the poison”. One example is lima beans which naturally contain toxic cyanide ion, but lima beans aren’t toxic as the dose of cyanide is too small.
 
Arsenic has historically been a component of intrigue. In 15th century Italy the Borgia family waxed powerful. Lucrezia and Cesare were among the children of Cardinal Rodrigo Borgia (who became Pope Alexander VI- obviously things in the church were different in those days!) Lucrezia was said to be a very effective poisoner as she had learned how to concoct lethal Arsenic potions which were undetectable in food or drink. Arsenic-laden wallpaper
 
Napoleon may have been done in by Arsenic, but not by an intentional poisoning. His villa on the island of St Helena had wallpaper colored with Sheele’s Green, a pigment made from Arsenic. In moist air a mold can grow on the wallpaper and convert the Arsenic to a volatile form. It appears at least for Napoleon that not the butler but rather the wallpaper did it. Another Arsenic pigment called Emerald Green may have impaired the health of Cezanne, Van Gogh, and Monet among others.

Emerald Green Paint Pigment

Emerald Green Paint Pigment


 
Some women in the Victorian era would eat small amounts of Arsenic to produce a pale complexion. Tanned skin in those days indicated that one worked in the fields and was therefore of a lower class.
Now back to Apple juice. Any Arsenic in juice is an issue if for no other reason that juice is a mainstay of many children. Two questions come to mind. Where did the arsenic come from and is there enough Arsenic in the right form to be a risk to health?

 Generally speaking the Arsenic is coming from the soil in which the fruit is grown. It can be in the soil naturally or due to use of Arsenical pesticides applied to the soil. Lead Arsenate was used in the United States until the seventies. Arsenic is very stable and could persist in soils for many years. Another source may be China, where environmental regulations are lax at best. Over half of the Apple juice sold in the United States now comes from China.

The amount of Arsenic measured recently in some of the juice samples does exceed the World Health Organisation’s suggested limit for safety. However the method of measurement included both toxic inorganic and relatively nontoxic organic Arsenic. When only the toxic form is considered the level appears to be safe. The FDA has been monitoring arsenic in Apple juice for decades and sees no threat to public safety based on these findings.

Pollutant Emissions and Efficiency

The answer to the question in the real estate business about property is always “location location location.” Similarly, the answer to the energy utilization question is always “efficiency, efficiency, efficiency.”

Dr. Amory Lovins, a physicist and energy guru coined a term for it called the “negawatt.” A negawatt as opposed to a kilowatt is the energy you don’t use by being more efficient. Negawatts save rather than cost money, yet still provide the same service to a homeowner.

So why all this talk about negawatts and efficiency? The Public Service Commission (PSC) here in Arkansas will soon have to address new regulations, promulgated by the Environmental Protection Agency (EPA) intended to reduce the harmful effects of power plant emissions.

These rules will impact coal fired power plants most directly, and rightfully so. Burning coal for electricity generation releases the largest share of pollutants from any of the possible fossil fuels. For a given amount of energy produced, burning coal produces more Carbon Dioxide, Sulfur and Nitrogen Oxides, heavy metals, fine particulates, etc – all serious pollutants.

You might ask that if we throttle back the burning of coal and coal is cheap, then our cost for electricity production is going to go up. Not necessarily for two important reasons. First, the cost you see on your electric bill is only part of total cost.

The cost of impaired health due to exposure to the aforementioned pollutants is real but not accounted for. Likewise, the cost of environmental degradation from global warming is real. The cost of political instability due to global warming induced climate change is real. The Less coal we burn, the lower are these external costs born by society.

So how do we contain the directs costs? The second step is demand side management. Now we’re back to negawatts. The new EPA regulations call for lowering carbon emissions by 30% by 2030. We need to achieve about a 2% reduction per year to meet the standard. It shouldn’t be difficult to achieve this goal through efficiency improvements alone.

Nobody really cares how many kilowatt-hours they use, what they care about is having a warm in the winter, cool in the summer, well lit home. The less energy you need to achieve that goal, the lower will be the electric bill. A very cheap step is to check that ALL incandescent lights have been replaced by compact fluorescent bulbs, or even better now, Light Emitting Diodes.

philips-led-light-bulb

philips-led-light-bulb

Consider adding some solar panels to produce energy and lower the electric bill. The cost of PV systems has decreased drastically, 60% in just the last two years!

Check the attic to see if more insulation is in order. How old is your HVAC system? Newer equipment is much more efficient. If you have an older Heat Pump, newer is better, i.e. more efficient. Or consider a ground source heat pump which is much, much more efficient.

ground-source-heat-pump

ground-source-heat-pump

Some of these these efficiency upgrades can be expensive, but recent legislation can help. Most notable is the PACE law. The Property Assessed Clean Energy bill allows cities and/or counties to form Energy Improvement Districts which have the authority to assist homeowners to make improvements, the cost of which is then added to the property taxes at such a rate that the increase in property taxes is matched by a corresponding decrease is energy costs.

Efficiency, Efficiency, EFFICIENCY.

Waste to Fuel

Most transportation be it personal or commercial depends on liquid fuels. The availability of liquid fossil fuels is decreasing and the cost is rising, Our dependence on these transportation fuels will continue until batteries and the electrical grid are greatly improved.

The only current alternative to fossil fuel is biofuel, ethanol from corn and biodiesel from soy beans. Ethanol makes up a scant two percent of our liquid fuel needs, biodiesel less than that. The figure is even lower than that when you account for the fossil fuel energy inputs to the production of biofuels. We won’t see row crop biofuels making up a larger share of our fuel needs because of the negative environmental impacts and the fact that biofuels production drives up food prices.

fueling up

fueling up

Another source of biofuel could be to waste to fuel plants. There are already plants which burn garbage (solid waste) for the generation of electricity, consuming about fifteen percent of all solid waste. Although this does produce energy and reduce the need for landfills, it doesn’t help with transportation needs. There are also concerns about the environmental and health impacts of the combustion products.

Liquid fuels such as methanol and ethanol can be produced from solid waste but currently the process is less efficient and more costly. Solid waste consists mainly of cellulose from various plant products and fossil fuel derived items like tires and plastic. Other unexploited sources of feedstocks are agricultural wastes from farming and timber harvesting. Even grass clippings and leaves could be utilized.

These materials when heated to high temperatures produce a mixture of gasses. The gasses can be chemically manipulated with catalysts and turned into methanol. Another methodology utilizes just the cellulose component. The materials are treated with sulfuric acid to release the sugar which is then fermented by traditional methods to produce ethanol. Japan is currently using this technology to produce ethanol for blending with gasoline.

A model system for waste to fuel would look something like a plant sited near a current landfill. Municipal solid waste, agricultural wastes, and suburban wastes would all be brought to the processing plant where the materials would be separated . Materials which are unusable wold still be land filled. Process heat for the plant would be provided to a degree by burning methane captured from the landfill.

So how much fuel can we expect to get? Estimates vary wildly. How much useful waste can be collected, how much energy will be consumed in the process, and the efficiency of the conversion process are just some of the confounding variables. Estimates range from a few percent up to as much as thirty percent of our liquid fuel needs.

waste fry-o-lator oil to biodiesel processing equipment

waste fry-o-lator oil to biodiesel processing equipment

The biggest problem with waste to fuel strategies is the resource base. The best way to contain the rising cost of any and all fuels is to become more efficient. The easiest way to be more efficient is to reduce waste. That means a diminishing resource base. This may not be a business model that many will wish to pursue.

The only long term solution to our energy needs, regardless source or form is to use a lot less and produce what we need sustainably. We have to learn to live within our means.

exxon valdez oil

Oil Spill Du Jour

This week connects several events. The 25th anniversary of the Exxon Valdez oil spill, the first anniversary of the Pegasus pipeline rupture in Mayflower Arkansas, and a brand spanking new oil spill in the Houston Shipping Channel of coastal Texas.

On March 24th, just after midnight the Exxon Valdez, loaded with over 50 million gallons of crude oil steamed out of Prince William Sound. Before the supertanker cleared the sound however, the ship collided with a reef which tore open the single walled hull releasing about 20 million gallons of crude oil. Twenty five years later oil can be found under rocks around the beach of the sound.

Exxon Valdez attempted cleanup

Exxon Valdez attempted cleanup


In a very short time hundreds of thousands of seabirds, thousands of sea otters, hundreds of sea lions and whales, and even 47 bald eagles were killed. A robust herring fishery has yet to recover. Damage to the local economy was devastating. Bankruptcies of both businesses and individuals shot up, and many families had to leave their ancestral communities for lack of jobs.

On March 29th an ExxonMobil pipeline ruptured and began spewing crude oil into the yards and streets of Mayflower Arkansas. The estimated quarter of a million gallons of crude, actually a substance known as dilbit, came from the Tar Sands of Alberta Canada. It is a mixture of tarry crude oil known as bitumen and and a diluent of lighter hydrocarbons, hence the name dilbit. Over a score of homes were evacuated. The dibit ran down the streets and intimately into Lake Conway. The pipeline has been closed and my not be reopened due to it’s passage through sensitive areas such as the Lake Maumelle Watershed.

Mayflower, AR

Mayflower, AR

On March 22nd a barge tow was struck by another vessel, releasing just under a quarter million gallons of a material know as bunker fuel – essentially heavy crude oil. The material is so viscous that it requires heating to flow threw fuel lines to burn in ship’s engines. Because of the spill, one of the busiest shipping lanes in north America was closed. This shut down oil refineries that produce over ten per cent of the oil refined in the United States.

Oil covered Shore Bird

Oil covered Shore Bird

So what connects the events besides late March? Human error. Every one of these events were due to multiple errors. Double walled hulls on the Exxon Valdez, and better navigation could have prevented the disaster in Alaska. The closure of the Houston shipping channel could have been avoided by better management of shippers involved. The ship which collided with the barge was already under probation for other problems. Replacement of aging pipelines and more frequent inspections could have prevented the Mayflower spill.

There are over 20,000 oil spills reported annually to the EPA. Some are minor and some not so minor, but they point out just how common the events are. In aggregate the economic and personal losses are large and generally unaccounted for when we look at the price of fossil fuels. The level of collateral damage we are willing to accept to avoid changing our lifestyle is staggering.

atmospheric co2

Impermanent Permafrost

The planet passed a milestone by mid-May of 2013 – the atmosphere hit 400 PPM Carbon dioxide. The carbon comes from both natural and human caused sources. Decomposing plant matter releases carbon naturally whereas burning fossil fuels does so “unnaturally”. Plants remove carbon during the growing season, so there is a cyclic annual variation in total carbon in the atmosphere.

For hundreds of thousands of years there was a balance between winter releases and summer decreases. Beginning in the industrial revolution of the late 18th century, winter releases have exceeded summer decreases such that the average concentration has gone from about 280 to 400 PPM.

We have a new milestone this year. This year the winter release in the northern hemisphere reached 400 PPM, almost two months earlier than last year, March 12th to be exact. This is yet another measure of the accelerating pace of the change to the atmosphere.

Some who confuse weather with climate may claim that polar vortex indicates that global warming isn’t happening, but this is a weather phenomena that was peculiar to the eastern United States. California and much of the west coast saw exceptional drought and warmer than normal weather. The iconic Iditarod sled dog race from Anchorage to Nome was hampered this year by warm weather. Portions of the 1000 mile long course were free of snow and ice.

 2014 Iditarod

2014 Iditarod

Global climate computer models and recent observations show that the northern reaches of the planet are warming faster than areas closer to the equator. This can actually accelerate global warming due to certain feedback effects on the concentration of gases in the atmosphere.

The tundra is characterized as a treeless area where the subsurface soil remains frozen year round. During the brief summer the surface snow melts and grass and sedge grow. One might think that warmer weather and shorter periods of snow cover would be good for growth but in fact recent research suggest just the opposite. It appears that earlier snow melt and warming in the permafrost results in lower soil moisture and hence less photosynthetic productivity.

The warming in the arctic has other scary possibilities. Occasionally, reasonably well preserved but definitely dead whole animals have been recovered in the tundra. Scientists went searching for for smaller game and found a virus. The virus was found in tundra frozen for at least 30,000 years. The difference besides size is the fact the the virus was viable. The virus when thawed out was able to infect and kill amoeba.

giant virus

giant virus

The thawing of the tundra and its disruption by extractive industries stands a good chance of exposing animate life on this planet to disease vectors not seen for thousands of years or even never before seen. As just one example consider that smallpox, exterminated from the surface of the planet, could make a comeback. Some experts say that over the centuries it has killed more people than all other infectious diseases combined. The future is ours to protect or ruin.

waterfall

What Price Clean Water?

The Cuyahoga River last caught on fire in 1969, but had burned uncontrolled on numerous occasions dating back to the latter half of the the nineteenth century. The river flows north through northern Ohio and Cleveland into Lake Erie. Numerous industries discharged wastes into the river to the extent that at times the river was coated with several inches of highly flammable sludge.

Cuyahoga on Fire

Cuyahoga on Fire

The 1969 fire along with a growing environmental movement resulted in the passage of the Clean Water Act in 1972. The waters of the nation have benefited from the laws, but problems still exist, especially when it comes to our demand for cheap energy in the form of fossil fuels and even cheaper food.

In one of the ironies of our time, a chemical used to clean coal means that the drinking water of Charleston, West Virginia is not so clean. In January 2014 several thousand gallons of an industrial chemical leaked from a Freedom Industries storage tank on the banks of the Elk river, just upstream of the drinking water intake for several hundred thousand people. To this day, some residents of the area refuse to drink the water as it still smells faintly of licorice.

In North Carolina, the Dan River has recently been contaminated by a pipe failure from a coal ash containment pond owned by Duke Energy. The river and even groundwater are now polluted with sludge that is highly contaminated with Arsenic, a heavy metal that is both toxic and carcinogenic. There are fears that the massive 40,000 ton spill is not over as another pipe may be leaking.

What these Clean Water Act violations have in common is that both were easily preventable. Had the responsible corporations taken care of business, the spills would never have happened. And had the responsible regulatory agencies done their job the problems that caused these spills would have been prevented. But no, businesses don’t want to spend extra money and taxpayers don’t want to properly fund the agencies that provide oversight.

A similar disaster is brewing in Arkansas. In our case it is not the result of industrial use of fossil fuels but the industrial wastes from a confined animal feeding operation (CAFO.) The hog farm, the first of its type in the watershed of the crown jewel of Arkansas, the Buffalo National River, was permitted by a deeply flawed process. The Arkansas Department of Environmental Quality granted a general permit for the operation. It did not consider the sensitive location in the Buffalo watershed, nor consider the uniquely porous limestone geology of the Ozarks.

CAFO

CAFO

Thousands upon thousands of gallons of liquid wastes, urine and feces, are contained in two ponds. The permitted design required only enough free board to contain a 25 year rain event. When the dirt bank ponds are breached, they will likely fail catastrophically, releasing the wastes into Big Creek and a few miles downstream, the Buffalo River National Park. Even during times when the banks hold, the clay lined ponds are allowed to leak wastes through the soil. Because of the Karst topography, the wastes can make their way rapidly to pollute the nation’s fist national river. Its not a matter of if but when.

Why do we continue to set ourselves up for these kinds of disasters? Because of short sightedness. Because we just can’t seem to learn that proper regulation of industry takes careful oversight, and the funding to provide for it.

The Real Costs of Fossil Fuels

Arguments against sustainable energy sources always include the fact that they are taxpayer subsidized and so more costly than they appear. These kinds of claims have been expressed before, but it is always worth reviewing the subject. How about the subsidies for fossil fuels? The direct cost of a gallon of gas, the cost at the pump, is currently about three bucks a gallon. The indirect costs can add as much as another $10 or more to the real price of a gallon of gas, bringing the total to something like $15 a gallon.
The direct costs are easy to calculate and include the cost to find produce, transport, refine and distribute the gasoline. These costs will continue to rise as crude oil becomes more scarce. It is increasingly harder to find the oil. And what oil is found is in smaller fields, deeper in the ground, farther out to sea, or all of the above.
As an example of the extremes taken to find and produce crude oil, the BP oil spill in the Gulf occurred at a well in 5,000 feet of water,

BP oil spill

BP oil spill

which was to be drilled another 18,000 feet below ground for a total depth of about 23,000 thousand feet. That is more than 4 miles below the surface of the ocean. Existing leases in the Gulf will necessitate drilling in water twice that deep.
The real run-up on the price of a gallon of gasoline comes from the indirect costs which include, but are not limited to military, environmental and healthcare costs.
Military costs to secure access and transportation of foreign oil are difficult to calculate, but the Congressional Research Service estimated well over $100 billion per year. These cost estimates do not include the direct cost of two wars in the Persian Gulf region. Estimated addition to the cost of that gallon of gas: $4.
war for oil

war for oil


Indirect costs for healthcare come about from burning that gasoline. Much asthma, chronic obstructive pulmonary disease (COPD), lung cancer and heart disease can be attributed to air pollution from automobile exhaust. Additional healthcare costs in Los Angles due to air pollution are put at about $1,200 per person, per year. Nationwide, the estimate is $75 billion dollars per year. Estimated addition to the cost of that gallon of gas: $3.
What is hardest to calculate, but in the long term the most damaging is the cost to the environment.
Obvious costs include everything from lost profits and wages for tourism and fisheries in the gulf due to oil spills to various global phenomena. Some are quantifiable — others not. Insurance companies are at the forefront in trying to put a value on property losses due to climate instability.

global warming is triggering more severe storms

global warming is triggering more severe storms


Here is one example. The estimate to mitigate a one-meter sea level rise from global warming is about $250 billion. Increased droughts, floods, hurricanes and tornadoes are all costly and the predicted result of global warming. This is admittedly a guess — but, estimated cost to that gallon of gas: several more dollars per gallon.
Finally there is the incalculable cost of environmental degradation – loss of habitat and biodiversity. What is the value in dollars to maintain a stable environment for our children’s future?

Global Warming and Geopolitics

There is no doubt that humans are transforming the atmosphere. It is impossible to explain away the fact that burning fossil fuels and deforestation result in the considerable increase of heat trapping gases in the atmosphere. The planet is getting warmer and the oceans are becoming more acidic directly as a result of human activities. Further complications are shifting rainfall patterns, and more severe storms.

A secondary consequence of global warming is political instability. Some scientists have suggested that the “Arab spring”, the uprising in North Africa and the Middle East, was driven at least partially by food instability.

Arab Spring

Arab Spring

The cost of a loaf of bread rose steeply following a severe heat wave and drought in Russia in 2011. The political instability in the region has give radical groups such as Al Qaeda a wedge to further disrupt society and gain power.

Bangladesh, with a population of over one hundred-fifty million, depends on glacial melt in the Himalayas for fresh water much of the year. As glaciers recede, the slow metered flow of melt water changes from a somewhat constant flow to major rivers to alternating flooding torrents and droughts.

bangladesh

bangladesh

Further exacerbating the situation is the fact that much of region is at or near sea level. The combination of droughts, floods, and salinity from sea level rise could cause famine, driving the predominately Muslim population into predominantly Hindu India. Ethnic conflict would be likely.

The newest country in the world, South Sudan, came about after years of civil war in Northern Africa. The region has been stressed by an extended drought. Sudan is currently constructing a pair of dams on the Nile. Nearby Ethiopia is also constructing a dam on the upper Nile,

nile

nile

which has greatly increased political tensions with Egypt downstream. Filling the lakes behind these dams could take years and severely reduce the flow in the Nile downstream. Again the strife in the region is driven in part by a long term climate change in the form of droughts.

The loss of sea ice at the North Pole could also be a political game changer. Asian countries, principally china, are actively developing fleets of cargo ships designed to sail the polar regions, and will increase if not solidify their hegemony over international trade.

The CIA and other intelligence agencies recently commissioned a study by the National Research Council. The conclusion: climate change presents even more risk in an already unstable world. Not only is the pentagon studying the mitigation of global warming, they are also studying the relationship between climate, climate change, and political strife.

Lighting Technology

The phrase “She would rather light a candle than curse the darkness” came from a Eulogy given by Adlai Stevenson for Elanor Roosevelt. This is of course a metaphor, as the bringing of light refers to bringing knowledge to an unknowing hence dark world. Aphorisms aside, let’s be literal. Let’s talk about lighting technology.

There is good evidence that one of our ancestors, Homo erectus learned to control fire close to a half a million years ago. Fire provided heat, protection from predators, and light to extend the day into night. The campfire of Homo erectus was wood and provided much more light than heat. Light was a byproduct.

Technology expanded light production with the creation of oil lamps about six thousand years ago. Made from clay, lamps were found at numerous sites, and depending on location these were fueled by animal fat, vegetable oil or even petroleum oil from natural seeps. The related technology of candles came later, possibly originating in China about three thousand years ago. The Chinese candles were made of whale fat. Other materials for candles include tallow, beeswax, and contemporaneously paraffin, a solid petroleum derivative.

Kerosene lanterns, still in use in much of the world were common by the nineteenth century. Gas lamps, using gas as opposed to liquid developed about the same time and were popular as stationery light sources, e.g, street lamps.

All these light sources share one property – combustion. Burning something, combustion, is an exothermic process. Burning gives off heat, and if you give off enough heat you get (visible) light. Thomas Edison recognized that if you get something hot enough, whether burning or not, you get light.

Incandescent 16 Lumens per watt

Incandescent 16 Lumens per watt

His invention, the incandescent light bulb (ILB) employing electricity, revolutionized lighting and has illuminated the modern world since the start of the twentieth century.

The new revolution in lighting technology is the production of light sources much more efficient than incandescent bulbs. ILBs work by the heat, then light produced by resistance to the flow of electricity through the Tungsten filament. But it is an astoundingly inefficient process when illumination is the objective. Only about five percent of the energy consumed by an ILB produces light, the remainder is given off in the form of heat.

Luminous efficacy is measured by the product of the amount of light measured in lumens, divided by the energy to power it measured in watts. The luminous efficacy of an ILB is sixteen lumens per watt.
ILBs are cheap to produce but waste energy. More efficient are compact fluorescent bulbs (CFB).

a 100 watt equivalent clf uses about 28 watts

a 100 watt equivalent clf uses about 28 watts

These have a luminous efficacies of about fifty to sixty. They are therefore cheaper to operate but have a few drawbacks; they take time to reach full illumination especially at low temperatures, they aren’t dimmable, and they contain small amounts of Mercury which complicates disposal.

The most promising entry to inexpensive lighting are Light Emitting Diode light sources. They are everywhere already in electronic technology in the form of various indicator lights. These LEDs have now been ganged in groups to produce illumination with efficiencies of over one hundred.

100 watt equivalent LED uses less than 22 watt

100 watt equivalent LED uses less than 22 watt

LEDs don’t suffer from the deficiencies of other bulbs; they are very efficient, “instant on”, dimmable, cool to the touch, non toxic, and will become even more efficient as they are developed. The future for LED lighting is bright indeed.