(Source: NC Warn)
Financial crossover occurred in North Carolina, bringing new opportunities
Duke University has reported that solar energy costs are now cheaper than nuclear energy costs after a "historic crossover" in North Carolina.
The paper on this topic was written by John O. Blackburn, professor of economics at Duke University in North Carolina, and Sam Cunningham, a graduate student at Duke. The paper is titled "Solar and Nuclear Costs - The Historic Crossover," and shows that change in costs on both solar and nuclear energy has finally forced them to meet, and then solar
This is in reply to
Solar Supplement 02 Sep, 2010
Sri Lanka LOLC cuts grid use with solar power
As an Electrical engineer I can see the following.
Coal has its place and renewable and Solar has its place
The cost of grid power in domestic consumption >600 units/month is Rs 39/kWh for every additional unit. For units more than 180/ month also it is also high as Rs32.50/kWh! So solar rooftop power with FiT is a good option for high consumption domestic consumers(Large houses) with shade free roof.
My Comments on the article By Dr.Tilak
The said cost of solar PV installed is $3,750/kW
There are now thinfilm solar panels selling at $1/W and installed costs like $2,000/kW They have plant factors close to 35% in good sunshine areas with tracking
Modern good COAL power plants now costs more than $3,000/kW. There plant factors are around 85%. But they have very high maintenance and continues fuel cost!
The life of present solar panels are > 30 years. Many guarantee 80% of the initial output even after 25 years. There are solar cells working well even after 30 years of use
Also there are maintenance free solar panels which do not even need dusting and cleaning It cannot cost all that Dr.T.claims!
The modern Transformer less inverters have efficiency close to 99% there prices are very much lower than $1000/kW so the cost figures given in the article include solar and the imported inverters.
The new inverters need not be replaced every 5 years. Now they give a life guarantee of 20 years.
Solar panels work free of any further fuel costs as it only uses sun energy Where as the Coal plant needs Coal supply and today the FOB price is>$100/t
Typical thermal efficiency for Coal electrical generator Power plant in the industry is around 33% you can produce at 2.0 kW·h/kg
Today's price of Imported Coal is $100/t and the price is steeply rising like the "Peaking OIL" price!
If we are to spend 1 unit of energy in Oil to drill and bring it up refine and transport to place of use it is better not to get that 1 unit of oil. We are going deeper and deeper to get oil and even if there is oil we cannot take all the oil out!
With transport to Sri Lanka Cost of Coal will be $120/t if no taxes and duties!( If like Oil if taxed the costs can be higher than %150/t)
1t=907.kg so cost of coal for 1kWh is $0.5=Rs56 at the Generation point. There can be 10% Transmission loss!.
Where as the Distributed Generation by Solar will reduce the load on both Transmission and Distribution. This is an added advantage which also has to be valued and taken into account.
As thermal efficiency for Coal electrical generator Power plant in the industry is around 33%. The balance 67% of energy in COAL is sent as mostly heat to the atmosphere in addition to pollution by CO2,ASH, Sulfur, Nitrous oxide,,Mercury Antimony etc. At full load in a 500 MWe plant needs about 6,000 US gallons per minute (400 L/s).for cooling
Environmental problems of COAL are all well documented and the health costs are very very high. Water table getting effected and ash leakage in US has led to Billions in compensation!
These costs are not considered.in his analysis.
With CDM or Carbon trading we should be able to get $30 now for every ton of CO2 displaced
There are a number of adverse environmental effects of coal mining and burning, specially in power stations including:
* Generation of hundreds of millions of tons of waste products, including fly ash, bottom ash, flue gas desulfurization sludge, that contain mercury, uranium, thorium, arsenic, and other heavy metals
* Acid rain from high sulfur coal
* Interference with groundwater and water table levels
* Contamination of land and waterways and destruction of homes from fly ash spills such as Kingston Fossil Plant coal fly ash slurry spill
* Impact of water use on flows of rivers and consequential impact on other land-uses
* Dust nuisance
* Subsidence above tunnels, sometimes damaging infrastructure
* Coal-fired power plants without effective fly ash capture are one of the largest sources of human-caused background radiation exposure
* Coal-fired power plants shorten nearly 24,000 lives a year in the United States, including 2,800 from lung cancer
* Coal-fired power plants emit mercury, selenium, and arsenic which are harmful to human health and the environment
* Release of carbon dioxide, a greenhouse gas, which causes climate change and global warming IPCC and the EPA. Coal is the largest contributor to the human-made increase of CO2 in the air according to the
* There are several accidents in the Coal mines with so deaths every year. These cannot be valued!
CO2 emission is 202.8 pounds of carbon dioxide per million Btu OR 1.350 pounds CO2 per kilowatt hour = 0.61metric ton,kWh
by eliminating this by solar the Cost equivalent of this is at today's price of $30/.t= $4
One tC is roughly equivalent to 4 tCO2.
So Solar generation 1kWh eliminates 0.6t of CO2 and will get Rs 448 as carbon credit
Now you may please check how solar energy is better than Coal fired energy where possible in countries like Sri Lanka which has more than average 5.5 sunshine hours/day
Solar is definitely cheaper and environmentally better
Social cost of carbon
The social cost of carbon (SCC) is the marginal cost of emitting one extra tonne of carbon (as carbon dioxide) at any point in time. To calculate the SCC, the atmospheric residence time of carbon dioxide must be estimated, along with an estimate of the impacts of climate change. The impact of the extra tonne of carbon dioxide in the atmosphere must then be converted to the equivalent impacts when the tonne of carbon dioxide was emitted. In economics, comparing impacts over time requires a discount rate. This rate determines the weight placed on impacts occurring at different times.
According to economic theory, if SCC estimates were complete and markets perfect, a carbon tax should be set equal to the SCC. Emission permits would also have a value equal to the SCC. In reality, however, markets are not perfect, and SCC estimates are not complete (Yohe et al.., 2007:823).
An amount of CO2 pollution is measured by the weight (mass) of the pollution. Sometimes this is measured directly as the weight of the carbon dioxide molecules. This is called a tonne of carbon dioxide and is abbreviated "tCO2". Alternatively, the pollution's weight can be measured by adding up only the weight of the carbon atoms in the pollution, ignoring the oxygen atoms. This is called a tonne of carbon and is abbreviated "tC". Estimates of the dollar cost of carbon dioxide pollution is given per tonne, either carbon, $X/tC, or carbon dioxide, $X/tCO2. One tC is roughly equivalent to 4 tCO2.
Estimates of the SCC are highly uncertain. Yohe et al. (2007:813) summarized the literature on SCC estimates: peer-reviewed estimates of the SCC for 2005 had an average value of $43/tC with a standard deviation of $83/tC. The wide range of estimates is explained mostly by underlying uncertainties in the science of climate change (e.g., the climate sensitivity), different choices of discount rate, different valuations of economic and non-economic impacts, treatment of equity, and how potential catastrophic impacts are estimated. Other estimates of the SCC spanned at least three orders of magnitude, from less than $1/tC to over $1,500/tC. The true SCC is expected to increase over time. The rate of increase will very likely be 2 to 4% per year.
China Racing Ahead of U.S. in the Drive to Go Solar
China Tries a New Tack to Go Solar
It’s official – Coal power plant emissions can kill, worsen our health and destroy the environment. The fatal effects of coal emission is no longer “just theory” or “myth”. They have been established in the findings of fact by the Federal District Court of the USA, in
On 13 January 2009, District Judge Lacy H. Thornburg declared that air emissions from TVA’s coal-fired plants located in
After hearing the expert evidence presented by all the parties to the case (including the coal power plants’ operator), the Judge declared that coal emission could cause devastating effects on human health and the environment. The Judge also ordered TVA to install pollution control mechanisms in 4 of its coal power plants.
Among other things, the Judge declared that (in summary):
a) The process of combustion inside an the plant boiler causes the coal to undergo chemical changes, which release nitrogen, sulfur, and mercury;
b) These chemical elements go on to form dangerous chemicals such as nitrogen oxide (NOx), Sulfur dioxide (SO2), Ozone (O3) and tiny particles called PM2.5, before or after being released into the atmosphere.
c) Although most of these dangerous chemicals were captured or treated within the coal power plants, not all of them are prevented from escaping the plants.
[Therefore, some of them are bound to be released into the atmosphere, causing devastating health and environmental effects as a result.]
d) In addition to forming ozone, NOx in the atmosphere can also form nitrate (NO3). Likewise, SO2 in the atmosphere tends to turn into sulfate (SO4) or a variation thereof, such as ammonium sulfate or sulfuric acid.
e) Nitrate and sulfate are significant components of a group of tiny airborne solids that can be found in the atmosphere. Collectively, these solids are commonly referred to as PM2.5, because they have a diameter of 2.5 microns or less, which is much more tiny when compared to a human hair (50-70 microns), dust, pollen, and mold (about 10 microns).
[At least 20 times tinier than our hair... This means that it could be very easy for PM2.5 to penetrate into human lungs/respiratory systems.]
f) Portions of atmospheric sulfate, nitrate, and other PM2.5 components remain in the air for long periods of time. Other portions travel to the earth’s surface through a variety of processes known collectively as acid deposition. For example, wet acid deposition occurs when atmospheric PM2.5 unites with water precipitation in the form of rain, hail, or snow. (i.e. “acid rain.”) Dry deposition, by contrast, occurs when PM2.5 travels to earth without uniting with water. Finally, a third kind of acid deposition is cloudwater deposition, which occurs most frequently in mountainous areas because they are prone to be foggy or immersed in clouds. In this process, PM2.5 unites with water droplets in clouds or fog, which then deposit on forest canopies and other surfaces.
g) There are ways available for coal power plants to decrease much of the emissions of these dangerous chemicals, up to 40-98% (depending on the type of chemicals), but they are very costly, and cannot completely eliminate the emission of these chemicals.
h) Even though the emission from these coal plants were at or below the “National Ambient Air Quality Standards for Particulate Matter” set by the United States’ Government, they are still bad enough to cause fatalities and destructions. The Judge’s actual words:
“PM2.5 exposure has significant negative impacts on human health, even when the exposure occurs at levels ****at or below**** the NAAQS.”
“Nonetheless, based on the totality of the evidence, the Court finds that, at a minimum, there is an increased risk of incidences of premature mortality in the general public associated with PM2.5 exposure, even for levels ***at or below*** the NAAQS standard of 15 ?g/m3 .”
“Half of a microgram of impact is very significant amount of impact. As noted above, the NAAQS for PM2.5 is 15 ?g/m3, and very negative effects on human health, visibility, and the environment can result at levels well below 15 ?g/m3.”
[So, the safest way to ensure the health of the people is to avoid these emissions altogether – i.e. CANCEL any more coal power plants, setting any “emission standered will not do”!!]
i) Exposure to – and inhalation of – air containing PM2.5 is 90-100% certain to cause premature mortality in humans. Specifically, PM exposure and inhalation can have the following effects on human health, any or all of which can lead to premature death:
(i) Systemic inflammatory response. PM inhalation causes pulmonary inflammation, which in turn tends to cause a more general system-wide inflammation in the body. This inflammation impacts platelet function, which contributes to the development of blood clots – a common cause of heart attacks and strokes.
(ii) Vascular reactivity. Systemic inflammation can also cause changes in vascular activity that decrease the amount of blood flow to important organs, including the heart and brain. Specifically, it affects the ability of blood vessels to remain sufficiently dilated for adequate blood flow to tissues. Such blood vessels also become less responsive to drugs designed to increase blood flow – including coronary blood flow.
(iii) Cardiac rhythms. PM inhalation also causes neurological changes affecting reflexes and autonomic control of cardiac rhythms. This can result in heart rate variability and ultimately arrhythmia, the immediate cause of death in most fatal heart attacks.
(iv) Infant mortality. There is a growing body of evidence that infant deaths can be linked to changes in ambient PM. Such infant deaths are attributable to respiratory problems and sudden infant death syndrome (SIDS).
(v) Other negative but non-fatal health effects: Increased incidence of asthma, chronic bronchitis, and other cardiopulmonary illness. The Judge’s actual words:
“After reviewing the totality of this evidence, the Court is convinced that exposure to PM2.5 – ***even at or below*** the NAAQS of 15 ?g/m3 – results in adverse cardiopulmonary effects, including increased or exacerbated asthma and chronic bronchitis”
“These negative but non-fatal health effects result in numerous social and economic harms to North Carolinians, including lost school and work days, increased pressure on the health industry due to extra emergency room and doctor visits, and the general loss of well-being that results from chronic health problems.”
[The emission of these dangerous chemicals could destroy our economy, INSTEAD OF helping us
j) Causing the formation of Ozone (O3), which, like PM, is associated with premature mortality in humans. More long-lasting effect of ozone exposure is increased airway inflammation. The increase in inflammation exacerbates asthma symptoms and increases negative responses to pre-existing allergens.
“If a person’s asthma and accompanying lung inflammation remain uncontrolled for more than two or three years, the person can develop irreversible scarring on his or her lungs, to a point where 10% to 60% of lung capacity is irretrievably lost.”
“It is well-established in the scientific literature that ozone contributes significantly to these bad health effects, ***even at or below*** NAAQS levels.”
k) Ozone formation is faster on hot, sunny days than on cool, cloudy days.
[This could mean that particles emitted by coal power plants are much more devastating in a tropical area like Sri Lanka than in temperate Western countries. If coal power plant emissions are already causing so much damage to these temperate countries, imagine what it would do to Sri Lanka?]
l) Destroying and Endangering our Environment, Natural Treasures, Drinking Water and Agriculture
“Acid deposition in the form of sulfate, when deposited on the ground, lowers the pH of the soil – that is, it makes the soil more acidic. Once the acidity of the soil reaches a certain threshold, aluminum occurring naturally in the earth’s crust is mobilized. This aluminum is toxic to the ecosystem. For example, it clogs (and eventually kills) the fine roots of local vegetation, including trees, making it more difficult for the overall root systems to absorb water and nutrients from the soil. This process, in addition to inhibiting healthy growth, also exacerbates the damage caused by any droughts that may otherwise occur.”
“Sulfate also removes magnesium, calcium, and potassium from the soil. Id. at 214-15. These nutrients are essential for healthy forest growth. Id. at 215. Calcium, for example, is the primary component of cell walls in vegetation; and magnesium is central to photosynthesis”
“Acid deposition, if it occurs anywhere near the watershed of running water, also degrades water quality by lowering pH and increasing aluminum content.”
“Ozone in sufficiently high concentrations can damage plants, including commercial crops as well as natural-grown vegetation.”
m) Cloud our sky and reduce our visibility. The Judge says:
“PM2.5, especially SO2, has significant effects on visibility due to its efficient scattering of light. An observer of a scenic vista would experience this scattering of light as haze.”
“PM2.5 haze and other air pollution impacting visibility at these vistas creates a difficult problem from both a social and economic
please note what is happening in China and India
n) These dangerous emissions could affect even far away towns and areas.
[Which means, the WHOLE of Sri Lanka is NOT safe!]
The Judge says:
“Emissions of primary pollutants have the greatest negative impacts in the areas closest to the source itself. Unbiased studies show that emissions reductions in a particular state will generate the most benefit within that state.
Nonetheless, emissions from a source located outside a state, particularly an upwind source, can still have significant impacts on that state’s air quality.”
Like to see the comments from viewers please