Static Electricity

Static electricity is an electric charge built up on persons or objects through friction. It is most familiar as an occasional annoyance in seasons of low humidity, but can be destructive and harmful in some situations. When working in direct contact with integrated circuit electronics, or in the presence of flammable gas, care must be taken to avoid accumulating and discharging static electricity.

Static electricity is electricity that does not flow in a current. Static electricity generated by rubbing two nonmagnetic objects together. The friction between the two objects generates attraction because the substance with an excess of electrons transfers them to the positively-charged substance. Usually, substances that don’t conduct current electricity (insulators) are good at holding a charge. These substances may include rubber, plastic, glass or pitch. The electrons that are transferred are stored on the surface of an object.

Materials Causing Charges

It is created by putting certain materials together and then pulling those apart causes excess electrical charges to be created on their surfaces. This can be done by pushing them together and pulling them apart or by rubbing the materials together, which is the main way it is created.

Excess of Charges

Most matter is electrically neutral. That means its atoms and molecules have the same number of electrons as protons. If a material somehow obtains extra electrons and attaches them to the atom’s outer orbits or shells, that material has a negative (–) charge. Likewise, if a material loses electrons, it has an excess of positive (+) charges. The electric field from the excess of charges then causes the electric effects of attraction, repulsion or a spark (lightning).

Stealing Electrons

According to Solar System Model (or Bohr Model) of the atom, electrons are in orbits or shells around the nucleus. A maximum number of electrons are allowed in each orbit. Forces in each atom seek to reach that maximum number, such that if an element is just one electron short of the maximum amount in its outer orbit, it would try to “steal” an electron from another element that may be just starting its outer orbit. This is the basis of chemical reactions.

Adhesive Molecular Force

An electric charge will also tend to hold two different materials together. In that situation, the force is called the adhesive molecular force. When different materials are pressed together and then pulled apart, the adhesive molecular force pulls electrons from material unto the other. This creates the phenomenon known as “static electricity”.

You can see this electric charge effect with a piece of Scotch tape or similar tape. First verify that it is not attracted to your finger. Then stick it to some surface and then pull it off. Put your finger near the tape and it will now be attracted to your finger, showing that there is an excess of charges on the tape.

Despite their small size, protons and electrons carry an electrical charge. Protons carry a “positive” charge, while electrons carry a “negative” energy charge.

Usually, the two different charges balance each other out, and nothing happens. But when two objects with like charges (all positive or all negative) come together, the charges repel and the objects move away from each other. Objects with opposite charges attract each other because the different charges want to enter a state of balance with each other.

Objects can get a negative charge by picking up electrons from other objects. For example, when your shoes scuff against the rug, your shoes are actually picking up electrons from the rug. The electrons fly over your body, giving you a negative charge.

Your new electrons fly over your body because they are looking for a positive charge. If you touch a metal doorknob, the electrons on your body will leap into the metal, attracted by the protons there. The transfer of electrons is actually a small electrical current, and produces the tiny electric shock you feel called Static electricity.

Lightning is similar, except on a much bigger scale. Both lightning and an electric charge happen because of the attraction between the opposite static electricity charges.

Not friction

Although you can create an electric charge by pressing materials together and pulling them apart, rubbing them together works even better, except in the case of something sticky like tape.

One unfortunate result from saying that rubbing materials creates this electric charge is that most people think that friction causes the charges to build up. It is not friction that causes the spark; rather it is the adhesive forces that pull off electrons.

Dry human skin and rabbit fur have the greatest tendency to give up electrons when rubbed on something and become positively (+) charged. Teflon and vinyl have the greatest tendency to become negatively charged (-) when rubbed. If you want to create it, rubbing fur on Teflon should give the best results.

In conclusion
It occurs when there are an excess of positive (+) or negative (-) charges on an object’s surface. You can create a charge by rubbing certain materials together. It is not caused by friction. The position of the material in the Turboelectric Series determines how effectively the charges will be exchanged.

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Solar Sector Moving Forward In 2013

Solar energy sector should expect good things to come its way in 2013, even despite the so much talked about Solyndra bankrupt  This is because solar energy industry is the fastest job generator in nation, and therefore one of the few bright spots in overall very dark economy.

The last thing US government needs right now is yet another industry going down the drain and this is exactly what will happen if government fails to show continuous support to solar power in 2013.

Home Power Generation

Micro-generation refers to the stand alone generation of low carbon heat and/or electricity and more and more people could be looking into this option in the future to ensure reliable energy supplies to their homes and help reduce damaging emissions into the environment.


1. Solar

Solar PV (photovoltaic) uses the sun’s energy to create electricity to run appliances and lighting. This doesn’t mean it needs to always be sunny for the electricity to be generated, as it relies simply on daylight. This option uses solar cells, usually placed on the roof, and made up of layers of semi conducting material. An electric field is created when the sun shines on the layers of the cells, causing electricity to flow. The stronger the sun, the more electricity is produced.

The pros of Solar panels or tiles include: No greenhouse gases released and low carbon dioxide emissions. They are not too obtrusive as panels can go onto the roof and solar tiles can replace roof tiles and panels covering 10-15 sq m could produce about a third of an average family’s electricity – saving on standard electricity costs.

Panels used to be heavy but the latest PV technology is light weight, so doesn’t require reinforcement of the roof. C21e solar roof tiles replace conventional tiles and are more convenient as can be installed by any roofer or competent individual.
The latest PV technology is also ideal for cities as a large proportion of buidlings are perfect for solar power as technologies now allow a number of surfaces to generate electricity eg. solar cladding, louvres. The latest PV technology replaces conventional building materials, and makes full use of space exposed to sunlight. Shading can sometimes be an issue in built up areas where not enough sunlight is getting to the panels but not in the majority of cases.

The cons include the cost – an average domestic system could cost around £4,000- £9,000 per kWp installed, with most domestic systems usually between 1.5 and 2 kWp so you are looking at between £6,000 at the lower end and £18,000 at the more expensive end. Cost will vary as tiles are more expensive than panels and integrated panels are more than standard. Planning permission may be required so you will need to check with your local authority if considering an installation.

In an effort to encourage UK households to adopt solar energy the government has introduced the Feed-in Tariff scheme which effectively pays households for every unit of energy they generate through their solar installation. The government hopes that by doing this it can meet it’s commitment to increasing the UK’s total energy from renewable sources to 15% by 2020.


2. Small Wind Turbines

Most people are familiar with the sight of a wind farm, but you can also generate energy at home on a smaller scale with your own wind turbine. Electricity is produced by the wind turning the turbines blades, which then turns a rotor.

At the moment wind turbines for urban locations are not really readily available, but should be developed within the next few years. The reason for this is that the turbines work best at height as wind speed is higher so space is needed – no obstructions from other buildings and trees etc.

Pros include clean power generation, cheaper than solar generation and there should be no shortage of wind, especially in coastal areas. Cons include visual impact considerations, some people see the turbines as an eyesore and they will usually require planning permission from local authority. Cost is also an issue, although cheaper than solar, wind turbines are by no means cheap. A 1kW system will cost around £3000 with larger systems in the region of 1.5kW to 6kW would cost between £4,000 – £18,000 installed. (A a typical domestic system would be 2.5 – 6 kilowatts, depending on the location and size of the home).



3. Biomass

Biomass, also referred to as Bioenergy or Biofuels refers to the burning of organic matter, e.g. plants, agricultural waste to make energy or heat.
It is a relatively clean energy generation method as the CO2 released during the burning is balanced out by the amount absorbed during the fuel’s production. Many different types of fuel can be used but for small-scale domestic applications of biomass wood pellets, wood chips and wood logs are usually used. Biomass is not really that practical for the average town or city household but if you are able to accommodate the equipment, biomass does have its benefits.

Biomass can be used to heat your home in two ways, either by the smaller scale stand alone stove with a 6-12 kW output fuelled by logs or pellets to heat the room or by a biomass boiler with an output of 15 kW which is connected to central heating and hot water systems. Pellets, logs or chips are used to fuel these. You will need a flue fitted and it must be the correct specifications for the fuel you are using.

Pros include, as the above two options, a cleaner, renewable fuel and cuting your energy costs by generating your own heat and hot water. There are also economic advantages the market for fuel providers is opened up. Using a local fuel source would be the most cost-effective.

The costs vary with the size and type of system but a guide is – stand alone room heaters cost around £1500 – £3000 installed. A typical 20kW (average size required for a three-bedroom semi-detached house) pellet boiler would cost around £5000 installed, including the cost of the flue and commissioning and manual log feed system of the same size would be slightly cheaper. Other considerations are sufficient space, a continual fuel supply and possible planning permission – your local authority will need to be contacted before a flue is fitted.

As there are added fuel costs with this method, it is recommended only really in areas without a gas supply.



4. Geothermal


This method of generation, also called ground source heat pumps utilise the natural heat of the earth. A few metres down, the soil in the UK maintains a heat of 11-12 C and by feeding a coil into the soil and transferring the heat from the ground into a building, heating and hot water can be produced. For every unit of electricity used to pump the heat, 3-4 units of heat are produced.

The advantages are that the system is cheap to run as you just pay for the pump. It is recommended for under-floor heating as this works at a lower temperature. It can be disruptive to install but for new developments it can be installed with other building works. If you are short of space it is not recommended as you will need space for a trench or borehole to accommodate the ground loop. Again, this is a good option if you are in an area where gas in unavailable.

The costs are quite high with a typical 8kW system costing between £6,400-£9,600 plus the price of connection to the distribution system. You also have to take into account the cost of running the system when it is installed.

Power Management System

Power Management is the systems engineering involved in designing ICs and systems to efficiently and accurately deliver electrical power to the various components in a system. It involves efficiently converting unregulated voltages derived from the AC line, batteries, or other sources to regulated, precise and protected levels. Power management ICs manage transitions between standby, sleep and high power modes effectively. As systems become more complex, PM ICs often include auxiliary functions such as Audio, Li-Ion Charging, LED drivers to reduce overall cost and size. Power Management devices help to extend battery life in portable products. These solutions support products that are popular in consumer (hand held/portable), networking and computing, wireless, automotive and motor control applications - especially for extremely specialized, high performance products.


System Management is responsible for the operation and control of generator facilities, transmission and distribution networks, and large customer retailer supply management including demand side management. It has a central role in the scheduling of generator and transmission outages, and manage the real-time operation of the power system.

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Renewable Energy

Renewable Energy is electric power that is generated from renewable sources of energy lsuch as: wind power, solar power, geothermal energy, and hydroelectric energy. Renewable energy is easily replenished by nature and is a cleaner, non-carbon polluting source of energy like various fossil fuels. Renewable Energy sources are often referred to as emerging energy technologies.

Recently, the cost of leading renewable energy technologies have dropped so much that renewable energy technologies are competing with traditional sources of energy. The best advice is to consider your options. Lots of intelligent information is available from a variety of leading sources, like renewable energy associations, consultants and wind and solar equipment manufacturers.

Renewable energy electricity production is expected to expand significantly over the coming years in the developed world. This represents an opportunity for developed countries (large electricity consumers) to develop and commercialize new and competitive technologies to the traditional "fossil fuel" based technologies and thereby manufacture products and offer services in support of a growing industry.

Renewable energy is power that is generated from natural resources such as sunlight (through photovoltaic solar cells), wind (through wind turbines), water (through dams and hydroelectric power plants), came from renewable energy sources, In 2006, about 18 per cent of the world's electricity consumption came from renewable energy technologies, with 13 per cent coming from traditional biomass, such as wood-burning. Hydroelectricity was the next largest renewable source, providing 3 per cent (15 per cent of global electricity generation, followed by solar hot water/heating, which contributed 1.3 per cent. Modern technologies, such as geothermal energy, wind power, solar power, and ocean energy together provided some 0.8 per cent of total electricity generation.

The term "renewable energy" may not be equal to the term “green” energy. This is because typically the term green energy refers to energy from renewable systems that are smaller than conventional, large-scale electric power generation, including various renewable energy systems. For example, some large-scale hydro-electric projects require large dams and vast reservoirs that flood huge tracks of wilderness. Conversely, low-capacity hydroelectric plants use "low head" water as it turns downstream in order to generate electric power. This results in less impact on the environment.

Although renewable energy is quickly replenished, some of these energies depend greatly on whether the sun is shining or the wind is blowing.

When renewable energy is converted into electric power production, it is often times transmitted into an electric power grid and joins the electricity "pool", including non-renewable energy sources of power. Government and electric utilities are working to increase the overall proportion of renewable energy electricity produced by renewable energy.

Governments and energy experts are taking a new interest in renewable energy for several reasons. Electric power production from various renewable energy sources produces much fewer global warming, carbon dioxide and other toxic pollutantts, which are having an impact on the world's changing climate. Also, renewable energy usually adds fewer other gaseous pollutants to the atmosphere, including the following:

sulphur dioxide and nitrogen oxide gases that form the largest compontents of "acid rain";
fossil fuel particulate matter, which combined with ground-level ozone, constitutes "smog" on hot summer days;
mercury, which is claimed to transformed in the environment into a highly toxic substance and a threat to all living creatures.
When the world uses low-impact renewable energy sources, we help to protect the environment. When large-scale non-renewable (fossil fuel) energy projects are developed, they have the potentiality to affect watersheds, migration animal and bird routes, etc.

Electrical Transformers

Electrical transformers are used to "transform" voltage from one level to another, usually from a higher voltage to a lower voltage. They do this by applying the principle of magnetic induction between coils to convert voltage and/or current levels.

In this way, electrical transformers are a passive device which transforms alternating current (otherwise known as "AC") electric energy from one circuit into another through electromagnetic induction. An electrical transformer normally consists of a ferromagnetic core and two or more coils called "windings". A changing current in the primary winding creates an alternating magnetic field in the core. In turn, the core multiplies this field and couples the most of the flux through the secondary tranformer windings. This in turn induces alternating voltage (or emf) in each of the secondary coils.


Electrical transformers can be configured as either a single-phase or a three-phase configuration. There are several important specifications to specify when searching for electrical transformers. These include: maximum secondary voltage rating, maximum secondary current rating, maximum power rating, and output type. An electrical transformer may provide more than one secondary voltage value. The Rated Power is the sum of the VA (Volts x Amps) for all of the secondary windings. Output choices include AC or DC. For Alternating Current waveform output, voltage the values are typically given in RMS values. Consult manufacturer for waveform options. For direct current secondary voltage output, consult manufacturer for type of rectification.

Cores can be constructed as either a toroidal or laminated. Toroidal units typically have copper wire wrapped around a cylindrical core so the magnetic flux, which occurs within the coil, doesn't leak out, the coil efficiency is good, and the magnetic flux has little influence on other components. Laminated refers to the laminated-steel cores. These steel laminations are insulated with a nonconducting material, such as varnish, and then formed into a core that reduce electrical losses. There are many types. These include autotransformer, control, current, distribution, general-purpose, instrument, isolation, potential (voltage), power, step-up, and step-down. Mountings include chassis mount, dish or disk mount, enclosure or free standing, h frame, and PCB mount.

Wind Power

Wind power can be an excellent complement to a solar power system. Here in Colorado, when the sun isn't shining, the wind is usually blowing. Wind power is especially helpful here in the winter to capture both the ferocious and gentle mountain winds during the times of least sunlight and highest power use. In most locations, wind is not suitable as the only source of power, it simply fills in the gaps left by solar power quite nicely.
Building a wind generator from scratch is not THAT difficult of a project. You will need a shop with basic power and hand tools, and some degree of dedication. Large wind generators of 2000 Watts and up are a major project needing very strong construction, but smaller ones in the 700-1000 Watt, 8-11 foot range can be built fairly easily. In fact, it is highly recommended that you tackle a smaller wind turbine before even thinking about building a large one. You'll need to be able to cut and weld steel, and a metal lathe can be handy