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ECG, VRA, GRIDCo must adopt right technical approach for lasting solution

Ecg Logo Min File photo: The Electricity Company of Ghana

Fri, 9 Apr 2021 Source: Peter Antwi Boasiako

In my recent interviews and articles written on the current issues with Ghana power supply, I have suggested various ideas/solutions that will help solve the power supply issues characterising certain parts of the country, especially the supply to Ashanti region (Kumasi in particular), including the suggestion that the ECG should embark on introducing effective Power Factor Corrections (PFC) - Capacitor Banks/Static Var Compensators (SVCs), at all substations so as to control the voltage level and reduce the huge power losses due to reactive loads in the system and by so doing, reduce or eliminate unnecessary monies paid by Gridco to VRA to cater for losses since energy generated cannot wholly be accounted for by the time it gets to the consumer.

The suggestion made seems to have drawn the attention of other Energy Experts, recommending same, as the report published by myjoyonline.com on 3rd April 2021 corroborates the fact that the power generation, transmission and distribution managers have been failing to anticipate rightly and invest the right amount of technical solutions that will deliver power efficiently and reliably.

The report quotes that, Ghana loses over $2.5m monthly for 38 Megawatts of power not consumed but wasted on the gridlines and distribution system due to the reactive power loss and failing to install Power Factor Correction capacitor banks with a total cost of $10 million at the substations.

The report further stated that, the GRIDCo/ECG failure to invest in this corrective equipment at substations has led to only 28 percent of capacitor banks installed for 944 megawatts load across the nation were functional as discovered in 2020 and that is costing Ghana $2.5m per month on reactive power loss.

This Substation Equipment – Capacitor Banks/SVCs, are basically used to control voltage level on transmission lines and in distribution system, by reducing drastically or eliminating voltage drops associated with inductive reactance. In other words, the Power Factor Correction (PFC) equipment is a technology which when installed allows the consumers to enjoy quality energy with required Power System parameters such as voltage, current to effectively and safely operate their home appliances without damage to such appliances and accompanying replacement of such appliances due to breakdown.

Reactive Power, essentially refers to the difference between the electricity supplied to customer and the electricity actually converted into useful power. What it also means is that, while the reactive power (kVAR) does not register on the true power (kW) or kilowatt hour meters, the utility's transmission and distribution network operators are bound to supply large power enough to cater for the total power demand, for both useful power and wasteful power (reactive power), which generates losses that GRIDCo need to account for, thereby reducing their cash inflows and at the end, can impede Transmissiom System expansion.

It's worth noting that, that such reactive power aids the useful power to operate the consumer appliances but that power is not sold in some parts of the world including Ghana hence the need to control it at the substations in order to fully harness the useful power by the time it gets to the customer end.

Now, gleaning from one of the recent press releases by Gridco, it stated that, “Our power system has grown in terms of demand. For the first time this year, we have crossed 3,000 Megawatt in terms of demand.”

Using the 3,000MW power supplied for hypothetical analysis, it means only 264MW of power supply (thus, 28 percent of 944MW) have functional PFC capacitor banks/SVC installed across the nation and for that, 38MW of the 944MW being the wasted power (power not sold) which is paid for at a cost of $2.5M per month paid for 38MW wasted power.

Abstractly, it also means that over 2,056MW (thus, 68 percent of 3,000MW) is the power supplied to Ghanaians without any form of Power Factor Correction equipment installed at-all across the nation, plus the 680MW (944MW – 264MW) with the dysfunctional capacitor banks installed. In total, over 2,736MW power supplied to Ghanaian consumers is without Power factor improvement.

Plausibly, it can be considered also that about 120MW out of the 2,736MW will be the amount of wasted power across the power supply system.

Now, if the 38MW unconsumed power costed Ghana $2.5M per month, then the 120MW wasted power will cost Ghana approximately $7.9m per month. This is a wasted money due to uninstalled/dysfunctional capacitor banks.

Thus, in 12 months, Ghana loses $94.8 million for wasted reactive power not consumed. The question is, whose responsibility is it to ensure that these substation equipment for power correction are installed and functioning to control the voltage level thereby reducing system losses?

What must be understood is that, allowing large reactive power demand in the system increases financial burden for all and unbearable pressure on the supply chain equipment to carry the large current. Failure to adopt effective Power Factor Correction, leads to increased voltage drop in the conductors which lowers the voltage at the user end, just like the voltage situation in Kumasi today.

The effect of PFC capacitor banks/SVC in distribution system ensures desirable energy efficiency and power quality without unnecessary load shedding application to improve voltage level, thereby inconveniencing the innocent consumer.

In my view, it will not be out of order if the Ministry of Energy questions the Heads of ECG and GRIDCo to explain as to why they have failed to ensure maintenance of the installed capacitor banks and not installed new ones to cover bigger megawatts, in order to reduce losses in the system.

Also, question the State Interests and Governance Authority (SIGA), having the monitoring and evaluation outfit to ensure efficient management and profitability of the States Owned Enterprises, for their failure to identify these important substation equipment been dysfunctional as the report suggests.

Isn’t it mind-boggling that, up until date Ghana as a country, still transmits power to long distance on its traditional 161kV High Voltage level, whiles majority of African countries have moved up to transmitting power as high as 400kV-500kV Ultra-High Voltage, for better efficiency and reliability, to meet the country’s growing demand.

This is main reason for the problems GRIDCo is facing with voltage control issues in Ashanti region, leading to the unnecessary load shedding in Kumasi, in particular. Yet, GRIDCo has failed to recognise the need to increase the country’s voltage transmission level to accommodate for any losses and ever increasing demand.

The primary purpose for power to be transmitted at high voltages is to increase efficiency. Other countries have seen this reason and have adjusted to transmitting ultra-high voltages in some African countries, in order to reap the benefits and position themselves for competitive advantage. Why hasn't Ghana seen the need to improve on its grid system to be competitive as well?

The essence of transmitting power on very high voltage is to have lower current accompanying high voltage transmission so as to have reduced resistance in the conductors as the electricity flows along the cables and, by so-doing reduce losses.

This means that thin, light-weight conductors can be used for long-distance transmission and still receive a desirable High Voltage at the end.

In comparison; since 2013, Kenya’s transmission level has been 220KV and then commissioned 400kV Ultra-High Voltage transmission in 2017.

Since 2009, Tunisia’s transmission voltage has been 225kV and added new 400kV grid in 2014.

Nigeria grid voltage transmission level has remained 330KV and increasing to Ultra-High Voltage.

In South Africa, around 60 percent of the country's high voltage network is at the 400kV level per reports in 2019, for efficiency, reliability and competitive advantage to grow their economy.

Ghana's Grid transmission Voltage is still 161kV for long distance transmission till date, whiles Zimbabwe transmits on 330, 400, and 420kV voltage levels.

Egypt, transmitting between 400-500kV Ultra-High Voltage, while the country has developed idea to construct a second interconnection with Libya, on 500kV line, in order to upgrade the interconnection with the Arab Maghreb countries. That notwithstanding, feasibility carried out for a 220kV interconnection with Sudan.

This is how important some African countries are seeing the need to improve on their power transmission and distribution system for reliability and efficiency. Our technocrats in Ghana who have worked with and/or advised various administrations over the years, and who should have prompted and pointed to the right direction to see need for investing in the upgrades of the system to achieve higher efficiency, have not lived up to expectation.

Typically, 220kV - 345kV HV is recommended level for over long distances transmission (to and beyond 240km) between the power generation plant and customer end, in order to reduce the amount of energy lost during the distance.

The Bui Dam plant failing to generate power due to lack of water inflow to augment the 161kV supply to Kumasi, has led to the uncontrollable voltage fluctuations and load shedding in Ashanti region, because no means to cater for the voltage dropped.

Obviously, Gridco never saw the need to develop plans, policies and programmes to upgrade Ghana’s transmission and distribution network.

Most often, the ordinary Citizen blame the Politicians for interference in institutions, but the fact is, these avalanche of ineptitudes at the management of state owned entities coupled with institutions that are given the Authority to set innovative policies to enhance the systems, facilitates the need for politicians to take over the failures of the institutions and use them to serve their whimsical parochial interest, to the detriment of the entire nation. We must demand performance and delivery from our civil servants and state owned enterprises.

It is though, refreshing to follow Ghana’s readiness to take the opportunity to join the 330kV West Africa Power pool project, starting from Nigeria through Benin to Togo, through Ghana to Burkina Faso and beyond. As Ghana connects to the 330kV high voltage transmission, it will help boost the voltage levels in Kumasi and supply to northern part of Ghana as well.

It is also commendable to observe the move by the new Ghana Energy Minister, Dr Matthew Opoku Prempeh, authorising GNPC to start the process for Gas pipeline construction and Ameri power plant to be relocated to Kumasi, to also help improve the voltage level in the capital city of Ashanti Region.

Columnist: Peter Antwi Boasiako