Power Converter 220V ac to 12V dc

A friend required an AC to DC converter to power a light circuit for a water fountain.
I have decided to design a circuit on his behalf.

Below is the required circuit diagram. I couldn't scan it because we currently experiencing high voltage electricity in my area; my bulbs and my scanner power adapter are gone; thus you have to manage a snap shot from my phone.

I hope this picture is clear enough.

Let me explain the circuit.

First, the 220V AC is stepped down to 12V AC using a transformer of appropriate wattage, the 12 V AC is rectified to DC using a bridge rectifier of appropriate wattage. Note, the DC voltage has ripples and these ripples have a low of 0V and a peak 16.97V - swinging from 0V to 16.97V.

A capacitor is connected in parallel to make the DC voltage eliminate ripples and the resistor across the capacitor is called the bleeding resistor. The capacitor should eliminate about 80% of the ripples. The resistor is used to discharge the capacitor whenever the the circuit is not powered up. Contact me for the calculation on values of the capacitor and resistor.

The voltage regulator 7812 is used to flatten the DC circuit completely on 12V. Since, it comes in different capacity; thus, I recommend that you use as many as possible in parallel to achieve the desired power requirement.

If you would like to have these lights switched ON and OFF automatically, don't hesitate to post comments below - it will come with a price though; we are all entrepreneurs.

Please Visit Dream Nigeria Blog

Please Visit Dream Nigeria Blog

Petroleum Products Scarcity

Petroleum Products Scarcity

Since the downturn of oil price in the middle of 2014, petroleum products have drop in price worldwide except in Nigeria. The official pump price is ₦87 per litre for PMS; however, today it goes for a minimum of ₦150.

People queuing for petroleum products.

There has been accusations and counter-accusation between the FG and Petroleum Product Marketers. The minister of Finance Ngozi Okonjo-Iweala has accused the Petroleum product marketers is blackmailing the FG, and ganging to stop the selling of petroleum products to consumers within the federation. She claimed barely a week after reaching an agreement to pay marketers over ₦200billion of claims, that the marketers are yet to be selling petroleum products to consumers; furthermore, that the marketers are demanding that she sign to pay another ₦159billion which is meant to be payment for differential due to the changes in exchange rate.[1]

Nigerians need petrol, diesel, etc to run their vehicles, to power their homes and to run their businesses. It is really biting hard on all Nigerian citizens and residents alike, individuals and companies. Some foreigners have joined to hustle for the search and purchase of the scarce commodity.[2] Furthermore, this petroleum product scarcity has forced aviation companies like Arik Air to suspend operation, Virgin Atlantic to divert to Ghana for purchase of aviation fuels. Not left out are telecommunication companies Airtel, MTN, etc; they are finding it difficult to power their equipments in order to provide efficient services due to this scarcity of petroleum products.

Petrol scarcity forces a foreigner to join the hustle - courtesy of Symphony007 of Nairaland.com

Why are we at the mercy of petroleum products marketers? Nigeria ranks the sixth largest exporter of oil, yet we import refined petroleum products for our consumption. We have four refineries in Nigeria, yet we are not feeling the impact of refineries in our economy; instead, we are being dependent on a group of petroleum marketers.

Back in 2012, most International Oil Companies IOC claimed that building refineries in Nigeria and the world at large was not profitable. This statement can be attributed to Mr Malcolm Brinded, the outgoing Executive Director of Shell Petroleum Development Company (SPDC). He based his claims on the information that there are surplus of refineries in the world; consequently, additional refineries in Nigeria will be at a loss to any entity venturing into the business. Furthermore, he claimed that it will be better to import refined products and pay the differentials in transport and exchange rates than to refine oil here in Nigeria.[3]

A petroleum refinery

Now we see the results of not developing our refineries. If the FG made plans to build new refineries or at least maintain the old ones so that they run at optimum capacity, we would not be in this problem we have found ourselves. Let us look at the advantages and disadvantages of refining our crude oil in Nigeria.

Advantages

• Capacity building and development of locality.
• Job creation for citizens and residents.
• Savings on logistics of importing refined petroleum products.
• Potential export of excess refined petroleum products.
• More business opportunities for entrepreneurs.
• Elimination of petroleum subsidy.
• Elimination of round-tripping (making claims on locally refined product with the assumption that they are imported).

Disadvantages

• Long-term business plan.
• Huge investment.
• Lack of quick returns.

Merely looking at advantages and disadvantages, we will realise that if we really want this country to move forward, then we need to stop looking at only short-term solutions, stop patronising conmen pretending to be businessmen.

On another note, Nigeria needs alternatives to these petroleum products. The demand for petroleum products in Nigeria is mostly for electricity generation. Our refineries are not working; we are not generating enough electricity to power the nation. Solar power is a very viable solution if we must develop and grow.

References

[1]          Fuel Crisis: ​​Okonjo-Iweala Accuses Oil Marketers Of Blackmail

[2]          White Man Looking For Fuel With Jerry Can In Nigeria

[3]          Why We Can’t Build Refinery In Nigeria -              Shell

http://dreamingnigeria.blogspot.com/2015/05/petroleum-products-scarcity.html

Electricity Business Challenges in Nigeria 3

What do you know about the current transmission and distribution system?

Which is more preferable in power systems, underground cable or overhead line?

The distribution and transmission network in Nigeria is mostly (90%) based on over head lines. The 330kV, 132kV, 33kV, 11kV, 415V lines are mostly based on overhead lines. In the distribution network, these conductors are usually placed at least 7 metres above the ground, suspended using concrete or wooden posts, far from human reach. Furthermore, these conductors are usually not insulated; however, they are isolated from the poles using porcelain insulators. In the transmission network, these conductors are placed at a higher height than that of distribution network due to the higher voltage in the network, and they are suspended using metallic structure which is composed of steel trusses. In addition, the conductors are suspended using glass insulators.

Advantages of Overhead Line

·         Lower capital costs.

·         Easy accessibility to the operators.

·         Quick time for repairs.

·         Easy upgrade.

Disadvantages

      ·         Easy accessibility to illegal connection touts and consumers.

       ·         Easy accessibility to vandals.

       ·         Highly susceptible to bad weather conditions such as wind, rain, snow, etc.

Given the current distribution system in Nigeria, where consumers engage in illegal connections, it can be said that overhead distribution lines can never work in Nigeria. The peoples’ orientation on energy theft needs to be dealt with appropriately. There is always a sudden trip-off of power supply whenever there is thunderstorm, rain or wind in Nigeria. Rain decreases the insulation provided by the surrounding and calculated separation of the conductors, this causes leakage currents which instantly triggers the safety measures and the control point. Thunderstorms, the electric discharge from a lightning bolt can trigger safety control systems as well. High wind speeds can wreck havoc on building, and overhead line structure. Furthermore, due to the problem of incessant vandalism on, it will be better to look into better way of securing the system as well.

Underground cables, most developed nations have phased out overhead lines; New York has no overhead line since 1890’s, Singapore has 100% underground network, The Netherlands has 100% distribution network, etc. So why can Nigeria embark upon underground cables distribution and transmission network. There are only few places with underground cables; example, parts of Sokoto State Polytechnic, Sokoto.

Advantages of Underground Cable

       ·         Not susceptible to bad weather conditions.

       ·         Unexposed to vandals.

        ·         Unexposed to illegal connection touts.

        ·         Low maintenance costs – if well panned and managed.

Disadvantages

                ·         High lifetime costs – needs to be replaced at expiry date to guarantee safety.

       ·         Upgrade needs an overhaul the installation.

       ·         Fault location is instantaneous but repair can take some while to be completed.

The beauty of underground cable network is that it prevents illegal connection, energy companies will definitely benefit from this because it will bring energy theft to a halt; however, this will involve a lot planning, dedication and investment. Once an underground cable has been buried and commissioned, it can last for up to 40 years and if its capacity is not exceeded, then it serve the community throughout its lifetime. No individual or group can successfully vandalise an underground cable, and bad weather conditions have no effect on it.

More coming soon....

Electricity Business Challenges in Nigeria 2

Do you need constant electricity?

Are you willing to bear the cost of constant electricity?

Prior to the advent of GSM in Nigeria, these same questions were on the minds of investor and every concerned individual in Nigeria. SIM cards sold for nothing less than NGN50, 000, how about handsets; they sold for nothing less than NGN30,000. The handsets in question are Nokia 3310, Siemens A50, Motorola; devices that hard less quality than your everyday scientific calculator. However, despite the cost, most Nigerians saw the value of GSM communication, they embraced it and our glorified dinosaur NITEL went caput because it refused to evolve.

With the success in the Telecoms industry in Nigeria, then an innovative solution for the Power industry should work as well. You must have read about the analysis of solar power that I posted on this blog. It is a viable solution if people can key into it.

Another phase of this solution is the total overhaul of the distribution network in Nigeria. The distribution network level has been bastardised, a lot illegal connections, inefficient wiring and wrong terminations plague the distribution network; there several losses incurred on the line. A new system that will be based on underground distribution network with zero accessibility to non-certified staff of the Operator distribution company should be installed. Furthermore, two-way electric meters should be installed as well.

Next, I will explain more on the advantages of underground distribution network.

Au revoir!

Electricity Business Challenges in Nigeria

How can we make this Solar Power solution possible in Nigeria?

Where can the everyday Nigerian get the money for Solar Power generation?

The first thing about a solution is accepting it as a solution. I have gone thru a quiz from friends on how I can recoup my money if I install it for consumer. However, my goal is not to install for a consumer but to install for very Nigerian and African at large.

There is one thing every Nigerian should know, any service rendered or commodity consumed must be paid for, else that service of commodity will cease to exist. Let us take an example, why has NEPA/ PHCN/DISCOs failed to provide power to Nigerians adequately? The answer is simple; most Nigerians prefer to consume electricity from the grid without making any payment.

Initially, it was a problem of lack of electric meters; this made NEPA/PHCN to send out estimated bills to customers. Note the phrase ‘estimated bill’, which customer in his/her right frame of mind will pay for an estimated bill; a customer has to the right to reject any estimated bill as far as he/she does not see the actual bill. Another problem with estimated billing is that the managers at the various distribution centres eagerly manufacture estimated bills for customers without any reference to energy that was supplied to the region they managed.  This coupled with electricity touting led to consumers making  illegal connections, it became a norm to the society, then the DISCO debt recovery agents failed in their duties by taking bribes from consumers and allowing them to use electricity without making any form of payment or having a concrete agreement to make payment.

Furthermore, with illegal connection now the norm, consumers of business categories hardly pay bills. Most welder shops, mechanic shops, barbing saloons, woodwork specialists shops, metalwork specialists shops, ladies’ hair dressing saloons, bukas(mini restaurants), beer pubs, mini guesthouses,  etc, do not have any electric meter installed at their places of businesses. These businesses run mostly of private generators which are fuel expensively, with the illegal connections, they utilise a few hours electricity from the grid; and at the end of the month, the DISCO agents will deliver an enormous energy bill to them - these bills are estimated bills. These businesses already pay a lot by running private generators, these enormous estimated bills without any evidence gets ignored; consequently, ignoring energy bills are now normal in the society.

In addition, even customers that are genuinely billed now ignore energy bills because, there is inadequate supply of electricity and why should one consumer pay when another is enjoying electricity illegally. As a result, when energy is utilised and no payment is made, the utility company NEPA/PHCN/DISCOs will definitely go into extinction like dinosaurs.

Coincidentally, other utility companies that were operated by the government has suffered the same fate – extinction, namely NITEL, NIPOST (operates below it capacity), State Water Corporations, etc. Other potential utility companies such Cooking gas companies, Internet companies are not developing as a result of this problem as well. NITEL was the sole operator of telecommunications in Nigeria prior to the year 2000. Having a telephone at home or in the offices was considered a luxury, less than 20% of the population had telephone at their homes. However, with the advent of GSM which was pioneered by ECONET, the spread of communication gadgets in Nigeria increased. Initially, to obtain a SIM card was expensive, and then came the competition MTN, Mtel, Globacom, Etisalat, and other CDMA networks. This competition eventually lowered the cost of the acquiring mobile phone subscription in Nigeria; now we have nearly 100% mobile subscription for every adult in Nigeria.

Now if there is a solution to telephone subscription in Nigeria, then we can as well develop the solution to the electric energy sector.

What are my ideas.......?

Electricity Business in Nigeria 2

How about businesses?

Solar Power for businesses, how?

We have seen the possibilities of solar power for homes, and without much further ado, let us delve into the business aspect.

Recall, that we mention about a cybercafé operating for 16 hours a day and it is powered by a 15kVA generator. We will compare generator and the solar power alternative. This cybercafé is assumed to operate every day expect Sundays; this implies that it will operate for 313 days in a year.

The beauty of this solution is that it is less expensive in the long run, the solar power can last for more than 16 hours a day and it can as well be operated on Sunday; thus, giving it a greater advantage.

This can further be applied to other industries such as banks, manufacturers, shopping malls, etc. 

Electricity Business in Nigeria

Can Electricity Business Prosper in Nigeria?

Are people willing to pay for the energy they consume?

Having pointed out some of the numerous problems in the Electricity problem industry, it will do a lot of good to proffer solutions before we delve into more problems.

Recall, I mentioned that over 60% of Nigerian households generate electricity using privately owned generators, and this is on continuous increase. To run a 2.5kVA generator continuously for 24 hours every day for one year, one will need to spend about ₦751,371.43 on petrol; furthermore if we include the capital expenditure and maintenance costs we will arrive at about ₦951,371.43. The lifespan of combustion based engines such generators is five years; consequently, running this generator continuously for five years, the owner will spend   about ₦4,156,857.14.

Now let us look at an alternative, solar power. Solar panels average cost is about ₦600 for 1VA (1W assuming power factor is 1). A solar power system comprises of the solar panels, the inverter for converting from DC to AC and the batteries for storage. The solar panels convert the light energy from the sun during the day to electrical energy in DC form. The inverter system has the inverter that converts DC electricity to AC electricity and the battery charger used to charge the batteries. The batteries are used to store energy during the day and the inverter will revert to the stored energy in the batteries for supply of power in the night. It worthy of note to mention that solar panel efficiency drop by about  1% or less  per year; thus, after twenty years solar panels can still be 80% efficient.

Below is a cost comparison between a 2.5kVA petrol generator and 2.5kVA solar power system courtesy of Yellowfin Energy Solutions LTD.

Look at the table above, we can deduce that solar has a very great cost advantage over petrol generators; 32% in savings over 5 years, 46% in savings over 10 years and 53% in savings over twenty years.  The only challenge here for solar power is initial starting cost and this is double the annual cost for petrol generator.

Thus, the pertinent issues here are starting capital, and repayment plan from the consumer. Most people I have informed of this idea are sceptical of such huge capital and the entrepreneurs are sceptical about making profits and securing capital investments.

More...

Electricity in Nigeria 3

Standards in the Electricity Industry?

Are there standards in the electricity industry in Nigeria?

Probably there were standards in the Nigerian electricity industry, or there are standards at some levels. Electricity is only experienced by consumers at distribution section, only the knowledgeable in the field are aware of the other sections of grid electricity. Well, we are glad most people do not know what goes on at the generation section, transmission section, sub-stations, etc; probably there could have been lots of more fatal incidents.

Caution! Electric Shock!

Why am I concerned about standards? At every corner in Nigeria, everyone is a technician or ‘engineer’ depending on the title that make the person feel important. A lot of buildings are not properly wired, the entire wiring are not done with reference to standards, sometimes these substandard connections cause electrocution, fires, and send faulty feedbacks to distribution transformers which end up degrading the transformer and the entire system.

Furthermore, another problem in our electricity is illegal connection. The people that do these connections are not usually trained on the job, they do the work based on what they pick in the streets, the connections are not properly terminated, the wires used are substandard and other gadgets used for connections are ignored and bypassed.

Another problem is the inefficient bill collection system. Most times, when agents of the distribution company go about their disconnection business, they tend to look for monetary kickbacks from consumers; consequently, some consumers end up not being disconnected despite owing the distribution company. This has reduced the authority rightful bestowed on these agents because they engage in illegal activities during their job.

Disorganised Wiring

In addition, some consumers engage touts to reconnect them back to the grid when there are disconnected by the distribution company agents. Other consumers take it further by illegally hooking back their lines on the distribution lines when the distribution company agents have left the premises.

Possibly, the reason why most people tamper with electrical connections is because we utilise overhead distribution system. It is a very open and unsecure system of electricity distribution.

Investments, investments, investments are need to achieve an efficient electricity system in Nigeria but how are the investors going to recoup their investments with all these lack of regulations and standards in the distribution sector.

More....

Electricity in Nigeria 2

Do you run a business?

Is your business dependent on electricity?

All about business

As a business owner, depending on electricity procured from the grid is a deliberate plan to terminate the business. Power supply to businesses without a dedicated transformer via the grid can last for about 2 hours maximum during business hours; consequently, businesses in Nigeria run mainly on petrol or diesel generators. Cybercafés, banks, saloons, copy centres, industries, just name them; every business in Nigeria never rely on power from the grid. However, the cost of powering these businesses is enormous and increasing due to the fluctuations in the cost of petrol or diesel.

Rising cost of oil

The volume of fuel most businesses consume in Nigeria is so huge that we will be wondering how we will be able to solve the problem lack of constant electricity in Nigeria. The government seems to be slow in securing investments into the power sector. Currently, Nigeria generates power at the rate of 4GW and if the country is going to make progress industrially and technologically, Nigeria needs to generate power at the rate of 100GW by 2020.

Let us take a look at a cybercafé that runs it business on a 15kVA generator; period of operation is from 0800hrs to 2000hrs, that is 16 hours. To run a 15kVA generator for 16 hours will at least 55 litres of diesel at the cost of ₦150 per litre of diesel. Assuming this cybercafé operates every day except Sundays, this implies that it will operate for 313 days in a year; consequently, the cost of fuel consumed over a year will be about ₦2,575,542.86. Note we are yet to include the cost of the generator and maintenance costs for the generator.

Where do we go next?

Electricity in Nigeria

Are you a Nigerian?

Do you reside in Nigeria?

Electricity in Nigeria

Being a Nigerian or residing in Nigeria can be very tough. If you have experienced Nigeria then you should be aware that Electricity is a very difficult commodity to come by and you must know that getting ten hours of electricity in Nigeria everyday is nearly impossible. Furthermore, the electricity bills are coming in every month with fixed and usage charges; and with the advent of privatization we will be expecting increment as well.  

Private generators in the same neighbourhood

In addition, over 60% of households Nigerians generate their electricity using privately owned petrol or diesel generators; also, private businesses that depend on electricity to function generate their electricity using generators. It will be more illustrating if we analyse fuel consumption and its costs.

Do you run a fuelled generator in your home? Probably, you run a 2.5kVA generator; but have you bothered to check on how much you spend running your petrol or diesel fuelled generator? A 2.5kVA petrol generator can run for seven hours on six litres of petrol, running this generator for seven hours every day, for one year will consume 2,190 litres for one year and this will amount to ₦212,430; note that this excludes generator costs, maintenance and logistics, and I assumed the cost of petrol is ₦97. Including maintenance and logistics costs, we will be having about ₦245, 000. Furthermore, an average home consumes about 18,250kWh in a year from the grid assuming if it receives power for ten hours daily for a year. Considering an average home within Port Harcourt Electricity Distribution Company PHEDC, it will ₦15.02 per kWh and a fixed charge of ₦700 monthly; consequently, an average home will pay about ₦282,515 for ten hours of electricity daily in a year. Therefore, for an average of 17 hours of electricity daily, an average home will be paying ₦527, 465 in a year; and, to have 24hours electricity an average home is expected to pay ₦772, 415 in a year.

Do you want to enjoy efficient power supply?

Are you willing to pay for your electricity?

Next, we will analyze power demand for businesses….

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