WHY ELECTRICITY?

Electricity just like any other product, has certain quality characteristics such as voltage level and tolerance, frequency, environmental performance, …But it also has very unique features.

The main characteristic of electricity is its high quality, and its resulting capability to serve practically any energy service (light, appliances, motion, electronics, heat) from a single system. The price to pay for this high quality is the conversion loss in the thermal power station, a loss that has been steadily decreasing over the past century, and is now approaching its thermodynamical limit. Serving all energy needs from a single system reduces cost of technical installations to the end-user. The capital becoming available could be used to invest in energy conservation (insulation), energy efficiency (class A+ appliances) or renewable generation.

Replacing electricity with less electricity

The efficiency of appliances to convert electricity into energy services is increasing steadily, and still has improvement potential. For example:

• Losses in refrigeration have been reduced historically by a factor 5, from the levels at the end of the 80’s to the best available technology in class A+ appliances (fig 3).

• Energy use for individual lighting applications can be reduced by a factor 5 or more . Modern lighting solutions are 50-100 times more efficient than candles.

• Distribution transformers, one of the most efficient machines ever designed by man, can still reduce losses by a factor 3-4 through the use of amorphous iron

• In motor driven systems (pumps, compressors, fans, washing machines, electric trains), it is possible to reduce losses by 30% on average.

Using electricity instead of other energy carriers to save primary energy and CO2 emissions

Because of its high quality, using electricity instead other energy carriers can have a boosting effect to save primary energy and reduce greenhouse gas emissions, even when including conversion losses in power generation:

• The use of high speed electric trains instead of air transport reduces primary energy use per passenger.km by a factor 3 and CO2 emissions by a factor 4.

• Using electric trains instead of diesel trains reduces CO2 emissions by a factor 4 and primary energy use by a factor 2.

• Electric vehicles are twice as efficient as vehicles with internal combustion engines.

• Efficient heat pumps, drawing heat from the underground require 20-40 kWh of electricity to supply 100 kWh of heat; they typically reduce final energy demand for heating by at least a factor 3 and primary energy demand by at least 25%.

• With induction heaters for cooking, 90% of (final) energy goes in the pan, compared to 55% for gas-fired cooking.

• Modern high temperature heating solutions for industrial processes can in some cases save up to 80% of primary energy and up to 60% of CO2 emissions through their efficient use of primary energy.

Electricity for an efficient economy

At the next level, electricity – the only energy carrier that can power the digital economy – enables system-level efficiencies, eliminating or drastically reducing the need for certain energy services:

• Teleworking, reducing the need to commute

• Videoconferencing or webconferencing, reducing the need for travel

• Heating controls for building energy management, ensuring buildings are only heated when needed

• Dimmable lighting systems, ensuring exactly the right amount of light in the right place at the right time

• Process control technologies, especially in industry

culled from http://www.earthtoys.com

HAPPY NEW YEAR! WHERE ARE WE GOING?

HI, THE END OF 2007 TOOK UP MY TIME ON MY FIRST POWER SUPPLY EBOOK AND I WAS UNABLE TO GET ACROSS ON THIS PLATFORM. HOWEVER I HOPE TO MAKE UP FOR THE LOSS OF TIME THIS YEAR.
HOWEVER I WANT TO SHARE THIS CLIP FROM http://pepei.pennnet.com/, SO THAT WE CAN REFLECT ON WHERE WE ARE GOING WITH OUR POWER GENERATION.


China's Three Gorges project generates 61.6bn kWh of electricity in 2007

2 January 2008 - China's Three Gorges hydropower project generated 61.6bn kWh of electricity last year, about 25 per cent more power than in 2006, according to operator China Three Gorges Project Corporation.

To date, the hydropower station had transmitted 207bn kWh of electricity to 11 provinces, municipalities and autonomous regions since it started operation in July 2003.
Currently, 21 turbines were operational with a total installed capacity of 13.3 million kW. Five more turbines would be added by year-end. The $22.5bn project was launched in 1993 in the mid-section of the Yangtze, China's longest river. Originally, its plan called for the 26 turbo-generators to produce 84.7bn kWh of electricity annually upon its scheduled completion in 2008. It was now to be expanded further to include six more turbines by 2012.

Hmm China is talking about an installed capacity of 13.3 Million KW while we are struggling to attain 10,000 MW.
Where do we go from here?

Inverters &Price

Above is a typical inverter that can be powered by a 12v battery to give 220v A.C output. The specifications are as given below:

Specifications

Output Wave Form	Modified Sinewave
No-load draw	<0.1a
Efficiency	Up to 90%
Input voltage range	11-15 VDC
Over voltage shutdown	over 15 VDC
Under voltage shutdown	under 10 VDC
Low voltage alarm	Audible at 10.6 VDC
Overload shutdown	Yes
Thermal shutdown	Yes
Short circuit shutdown	Yes
AC receptacle	Two 2-Prong
Warranty	1 year
Inverter weight	4 lbs
Dimensions (W x H x D)	5 x 2.25 x 7.25 in.

The unit has a continuous power of 400W and peak power of 800W .Some appliances or tools, such as ones with a motor, require an initial surge of power to start up ("starting load" or "peak load"). Once started, the tool or appliance requires less power to continue to operate ("continuous load". The price for this aside shipping is $49.99.

ELECTRICITY AND THE DARK CONTINENT

I have been off this page for quite sometimes now cause I have been busy with some other tasks. In recent times Power Supply has again become erratic and you sure can bet that a lot of Nigerians are once again calling for the heads of PHCN officials.
My primary focus on this page is to find alternative power schemes, that the average home user can easily secure to have continual power supply. You only need to see how dark the entire landscape appears once it's night time. In fact, I once saw a satellite picture of the World map showing properly illuminated outline of Europe, Asia and America, however the continent of Africa appeared very dark due to a very low luminance level. So I ask, is inadequate power supply one of the reasons for the 'dark continent' tag on Africa?
So how can the average home user in Nigeria for instance get electricity in the face PHCN inability to satisfy local consumptions?
I have previously on this page examined the choice of an Inverter circuit which helps you to generate electricity from batteries. The inverter goes along with a charger and battery cells. One could make locally depending on wattage for as low as N5,000 or import from Asia or America. I have come to discover that one could get good inverters cheaper from Asia than the US & the UK, but you need to really determine the type of applications you need the inverter for and also calculate your loads. (check previous posts for these). I got an inverter price list from China some months back and the lowest price was $37.
Comments are welcomed

DO YUO KNOW FUEL CELL ELECTRICITY?

A fuel cell is an electrochemical energy conversion device. A fuel cell converts the chemicals hydrogen and oxygen into water, and in the process it produces electricity.

With a fuel cell, chemicals constantly flow into the cell so it never goes dead -- as long as there is a flow of chemicals into the cell, the electricity flows out of the cell. Most fuel cells in use today use hydrogen and oxygen as the chemicals, unlike batteries. A battery has all of its chemicals stored inside, and it converts those chemicals into electricity too but eventually "goes dead" and you either throw it away or recharge it.

Types of Fuel
CellsThe fuel cell will compete with many other energy conversion devices, including the gas turbine in your country's power plant, the gasoline engine in your car and the battery in your laptop. Combustion engines like the turbine and the gasoline engine burn fuels and use the pressure created by the expansion of the gases to do mechanical work. Batteries convert chemical energy back into electrical energy when needed. Fuel cells should do both tasks more efficiently.

A fuel cell provides a DC (direct current) voltage that can be used to power motors, lights or any number of electrical appliances.

There are several different types of fuel cells, each using a different chemistry. Fuel cells are usually classified by their operating temperature and the type of electrolyte they use. Some types of fuel cells work well for use in stationary power generation plants. Others may be useful for small portable applications or for powering cars. The main types of fuel cells include:

Polymer exchange membrane fuel cell (PEMFC)
The PEMFC has a high power density and a relatively low operating temperature (ranging from 60 to 80 degrees Celsius, or 140 to 176 degrees Fahrenheit). The low operating temperature means that it doesn't take very long for the fuel cell to warm up and begin generating electricity.

Solid oxide fuel cell (SOFC)
These fuel cells are best suited for large-scale stationary power generators that could provide electricity for factories or towns. This type of fuel cell operates at very high temperatures (between 700 and 1,000 degrees Celsius). This high temperature makes reliability a problem, because parts of the fuel cell can break down after cycling on and off repeatedly. However, solid oxide fuel cells are very stable when in continuous use. In fact, the SOFC has demonstrated the longest operating life of any fuel cell under certain operating conditions. The high temperature also has an advantage: the steam produced by the fuel cell can be channeled into turbines to generate more electricity. This process is called co-generation of heat and power (CHP) and it improves the overall efficiency of the system.

Alkaline fuel cell (AFC)
This is one of the oldest designs for fuel cells; the United States space program has used them since the 1960s. The AFC is very susceptible to contamination, so it requires pure hydrogen and oxygen. It is also very expensive, so this type of fuel cell is unlikely to be commercialized.

Molten-carbonate fuel cell (MCFC)
Like the SOFC, these fuel cells are also best suited for large stationary power generators. They operate at 600 degrees Celsius, so they can generate steam that can be used to generate more power. They have a lower operating temperature than solid oxide fuel cells, which means they don't need such exotic materials. This makes the design a little less expensive.

Phosphoric-acid fuel cell (PAFC)
The phosphoric-acid fuel cell has potential for use in small stationary power-generation systems. It operates at a higher temperature than polymer exchange membrane fuel cells, so it has a longer warm-up time. This makes it unsuitable for use in cars.

Direct-methanol fuel cell (DMFC)
Methanol fuel cells are comparable to a PEMFC in regards to operating temperature, but are not as efficient. Also, the DMFC requires a relatively large amount of platinum to act as a catalyst, which makes these fuel cells expensive.

POWER FROM THE WIND IN INDIA

THE ARTICLE YOU ARE ABOUT TO READ SHOULD OPEN OUR EYES ON ELECTRICITY GENERATION IN AFRICA. INDIANS HAVE RECENTLY BEEN APPOINTED MANAGEMENT CONSULTANTS FOR NIGERIA"S TRANSMISSION COMPANY.

Wind Energy Is Growing In India

Power generation from wind has emerged as one of the most successful programmes in the renewable energy sector in India, even as this source of power is emerging as an alternative in fast-growing countries like India and China that are avidly seeking new energy sources.

With a rapidly growing economy, India’s energy needs are increasing, and are largely met by electricity from oil and coal fired power stations.

Industry analysts say that energy is a major input for overall socio-economic development and renewables are expected to play a key role in accelerating development and sustainable growth in the second half of the current century, accounting then to 50 to 60 per cent of the total global energy supply.

Reports suggest that wind generation is the fastest growing energy source in this decade and is expanding at 25 per cent per year. The industry experts recognises India as a new "Wind Superpower".

Available figures suggest that at the end of April 2007 India had 7113.6 MW of wind generating capacity and is the fourth largest market in the world. There are about a dozen wind pumps of various designs providing water for agriculture, afforestation, and domestic purposes, all scattered over the country. The states of Tamil Nadu, Karnataka, Andhra Pradesh, Gujarat, Rajasthan and Maharashtra lead in the field of wind energy

The growth of power generating capacity in India is today driven largely by increasing energy needs. The short gestation periods for installing wind turbines, and the increasing reliability and performance of wind energy machines has made the sector a favoured choice for capacity addition.

South region Tamil Nadu is the state with most wind generating capacity and western Maharashtra is second only to Tamil Nadu in terms of generating capacity. Suzlon has been heavily involved in the state.

The technical potential that is based on the availability of infrastructure, for example the availability of grid, is estimated to be around 13, 000 MW. In India, the wind resources fall in the low wind regime, the wind power density being in the range of 250 -450 W/m. It may be noted that this potential estimation is based on certain assumptions.

With ongoing resource assessment efforts, extension of grid, improvement in the wind turbine technology, and sophisticated techniques for the wind farm designing, the gross as well as the technical potential would increase in the future.

The leading countries in wind power installation are Germany, Spain, the USA, India, and Denmark. India has overtaken Denmark and is the fourth largest wind market in the world.

Wind turbines offered in India range from 250 kW to 2 MW capacities. Currently, there are 7 manufacturers of wind turbine generators in India.

According to a recent study from Emerging Energy Research (EER) entitled Asia-Pacific Wind Power Markets and Strategies 2006-2015, Asia-Pacific is emerging as the new frontier of the global wind industry, with the region expected to add over 46,000 MW of wind power in the coming decade.

In fact, the region’s market leaders - China and India - are expected to add over 41,000 MW between them by 2015. Together they will represent over 80 per cent of the Asian wind market during the period. Japan and Australia will each add between 150 MW and 450 MW per year, followed by less developed markets in South Korea, New Zealand, Taiwan, Pakistan and the Philippines.

Report further says that after a good year in 2006 in which around 1800 MW was added, India will retain its position as Asia’s leading wind power market in terms of total megawatts installed until 2015, when it will be overtaken by China.

Wind is a significant source of electricity in Denmark, Spain and Germany. Denmark generates 14% of its total electricity from wind sources, Spain 9% and Germany 5%. Among developing countries, wind was an important source of electricity in India, contributing around 1% to total electricity generation. Globally, wind generated electricity is still less than 1% of total electricity generation.

By T C Malhotra
http://www.poweralternatives.com/nc/power_stories/display_news/article/wind-energy-is-growing-in-india/492.html

UNDERSTANDING SOLAR ELECTRICITY

HI,
I AM SORRY I HAVE BEEN OFF THIS PAGE FOR QUITE SOMETIME NOW, BUT I CAN ASSURE YOU I AM BACK TO SERVE YOU BETTER, BECAUSE I STRONGLY BELIEVE IT'S HIGH TIME AFRICANS FIND WAYS OUT OF THE POWER SUPPLY DEBACLE THAT HAS TRULY KEPT THE CONTINENT DARK. SO I AM CONTINUING WITH ELECTRICITY FROM THE SUN. ENJOY READING AND PLEASE BE FREE TO POST YOUR COMMENTS


Energy from the sun for thousands of years has been harnessed for several purposes. However it is vital that we see this energy in three forms and properly understands the separate applications.

• Solar energy as passive heat: This we receive from the sun naturally and is taken into account in the design of buildings so that less additional heating is required.
• Solar thermal energy: Where the sun's heat provideshot water for homes or swimming pools.
• Photovoltaics (PV): where energy from the sun is employed to createelectricity which runs appliances and lighting.
  

NOTE! PV requires only daylight - not direct sunlight - to generate electricity.

MODE OF OPERATION
Photovoltaic systems through cells convert solar radiation intoelectricity. The PV cell consists of one or two layers of a semiconductingmaterial, usually silicon. When light shines on the
cell an electric field is formed across the layers, hence electricity flows. The flow of electricity is detemined by the light intensity
There are three main types of solar cells viz
• Monocrystalline: made from thin slices cut from a single crystal of silicon. This has a typical efficiency of
15 per cent.
• Polycrystalline: made from thin slices cut from a block of silicon crystals. This has a typical efficiency of around12 per cent.
• Thin Film: made from a very thin layer of semiconductor atoms deposited on a glass or metal base. This has a typical efficiency of 7 per cent.

The PV cells are connected together to form a module. Modules are then linked and sized to meet a particular load (electrical energy demand). The result is a PV array which supplies power to the building it is fitted on. If the building has mains electricity, any excess electricity can be exported to the national grid (as is the case in the US and some parts of Europe).
Alternatively, when demand is high, extra electricity can be purchased from the national grid through the utility companies in addition to the PV electricity. In the event of a mains power failure, PV arrays can be
used to charge batteries.
PV arrays are in a variety of shapes and colours,ranging from grey 'solar tiles' that look like roof tiles, to
panels and transparent cells that you can use onconservatories and glass to provide shading as well as
generating electricity.