Posted by News Express | 4 May 2020 | 1,472 times
One topic I found interesting in my undergraduate days was the electrical grid and its (dis)advantages. In many countries (including Nigeria), electricity is generated in large power generation plants (GENCOs). These plants send electricity to a central grid – a collection of electrical cables, transformers and switchgears – from where it is distributed to consumers. So, the “electricity” generated at the Egbin thermal plant in Lagos might be used by a household in Kogi State. But, the “electricity” generated in Kainji dam in Kogi will power a street light in Lagos.
The more I studied the topic, the less convinced I was of the usefulness of a national grid. A conviction I still hold.
Undoubtedly, central grids have advantages – increased reliability, spinning reserves, reduced fluctuation in load demand, etc. But, I believe that with the geographical variation in population density, per capita energy demand, and electricity use-cases across Nigeria, transiting to a decentralised grid in the long-term is better. That is my fourth paradigm shift to turn our darkness into light.
My last article discussed the first three: Government issuing meters to solve the metering gap; leveraging smart meters and law enforcement to block revenue leakage and sabotage; and incentivizing DISCOs to reduce ATC&C losses. While these can start immediately (or almost), grid decentralization requires more time, and for good reason.
Grid decentralization means shifting from a national grid to regional/state grids; or grids revolving around the eleven DISCOs, where the electricity generated by power plants in the coverage area of a DISCO is used to satisfy customer demand in that area. As less than half of the states in Nigeria have large scale GENCOs, “instantly” switching to a decentralized grid, will mean darkness in many states.
Thus, a phased approach, which I describe as DEED – Distributed Generation; Embedded Generation; Eligible Customer Distribution; and Decentralized Grids – is needed.
Distributed Generation: From the Nigerian Bulk Electricity Trading Company (NBET) February 2020 report, there were 25 grid connected power plants. But, in reality, Nigeria has millions of independent power generating plants – in individual houses, factories, hospitals …. even in the offices of DISCOs. Some (maybe even many) can produce a lot more power than the owners need. Increasingly, people install rooftop solar panels that generate more electricity than they need when the sun is up.
Why can’t we send these excess power to the DISCOs? This model – distributed generation – is a working model in some countries, especially with solar and wind power. By using smart meters and grids, and the right pricing mechanism, we can have two-way power supply between consumers and distribution lines.
Embedded Generation: In embedded generation, power plants supply customers in a specific area by connecting directly to an existing distribution network, bypassing the transmission network. For example, a solar power plant in Kaduna providing electricity to an estate already connected to the Kaduna Electricity Distribution Company but experiencing poor power supply. The power is sold to the DISCOs to sell directly to the specified customers.
Embedded Generation is already supported by regulation, and is good for industrial clusters, and rural communities connected to the grid but underserved.
But, scaling up embedded and distributed generation creates another problem – capacity of existing distribution networks. The existing networks of the DISCOs are constrained to supply about 6,000 MW of electricity, which is even less than current available capacity of GENCOs.
The next E – Eligible Customer Distribution – addresses the problem of spare capacity of the GENCOs and frees up the DISCOs to accommodate distributed and embedded generation.
In 2017, the then minister of power invoked a declaration that identified four classes of eligible customers, which under the Electric Power Sector Reform Act 2005, could purchase power directly from a GENCO, either through transmission and distribution networks or dedicated networks built to facilitate the transaction.
It helps reduce the burden on the DISCO network, and “promote growth through the provision of stable and secure electricity supply for industrial, manufacturing and large service enterprises”. It stimulates market competition, enabling quality improvement.
One drawback is that DISCOs could lose high paying customers (as Nigeria uses a progressive tariff structure), affecting their overall viability. Addressing the metering gap and tariff structure (see last article) will help to promote acceptance of this model.
Rigorous implementation of these three models over the medium term creates a pseudo- decentralized grid where large GENCOs sell power directly to large consumers, small GENCOs sell electricity to selected customers through the DISCO networks, and consumers sell electricity to distribution companies. These changes will ease the transition to our destination – a Decentralized grid – in 10 years or less.
With a decentralized grid, different states/regions will leverage different means of meeting their individual electricity demand – solar, wind, biomass, gas, hydro, etc. With a projected decline in costs for onshore wind and solar, electricity from solar and wind in area with high solar irradiation and wind speeds can become at par with power generation from gas power plants in areas with huge gas reserves.
To improve the robustness of these “independent” grids, tie-in points can be provided to other grids to allow power transmission across states during emergencies. This system of independent but interconnected grids provides flexibility and robustness.
But, does every consumer need to be connected to the grid to have regular electricity? No.
I believe the electricity needs of some are better served with minigrid or offgrid solutions. Leveraging offgrid and minigrid solutions is the last important piece of the puzzle in answering the call – “Let there be light”. My next article in these series will address that.
We are facing what is probably the greatest challenge since World War II – the COVID-19 pandemic, and its rising death toll, which has brought changes and suffering to many.
It is tough, but we must continue prioritizing slowing the spread. I encourage you to reach out to someone today, and share a positive word. If you can, look out for people to assist financially.
To the healthcare workers, emergency responders, and everyone risking their lives to keep us safe, fed, entertained, and powered, Chukwu gozie gi!
•Engr. Odinakachi Umunna is an energy and technology professional with experience in the media industry, public sector, and oil & gas. He can be reached at firstname.lastname@example.org
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