The increase in electricity demand in Nairobi, Kenya due to electric vehicle (EV) adoption will be moderate but unmanaged charging, especially from private and commercial EVs, could strain the power system, a new study warned. These factors can cause significant demand spikes during peak hours, it added.
In contrast, paratransit EVs, which primarily charge during off-peak hours, present a more favourable scenario without complex demand management, according to the report published in Scientific Reports October 17, 2024.
Customised demand management and infrastructure planning to support EV growth in African cities are the need of the hour, the authors of the report highlighted.
Researchers led by June Lukuyu from the University of Washington evaluated the techno-economic implications of charging demand management strategies, including avoiding battery energy storage costs and premature transformer replacements.
While private and commercial EV fleets can handle multiple trips on a single charge, only about 15 per cent of daily trips of paratransit e-matatus and e-buses can be covered on a single charge, necessitating frequent recharging in 20 per cent of the study area.
The researchers modelled the spatial distribution of private EV ownership — predicting that early adopters, and consequently home charging demand, will be concentrated in affluent areas. This was consistent with trends in countries with significant EV penetration.
For light-duty commercial fleets, charging demand is expected to be the highest in commercial zones, reflecting their typical use for goods transport and errands. Paratransit vehicles, like matatus and buses, operate on set routes connecting central and peri-urban areas.
Analysis revealed that while paratransit and commercial EV adoption may enhance grid conditions, widespread private EV uptake could strain the grid, significantly increasing peak electric load and transformer ageing, leading to higher outages and early replacement costs of up to $6.5 million within five years. This strain worsens with high EV owner range anxiety.
However, smart charging strategies for private and commercial EVs could mitigate these costs.
Implementing smart charging strategies could shift peak-hour demand to off-peak periods, enhancing system efficiency and reducing transformer replacement costs by 15-40 per cent, particularly for private EV home charging. While commercial EV charging also benefits from smart management, paratransit vehicles that charge during low-demand periods benefit less from these strategies.
Identifying high-demand areas is crucial for targeted infrastructure upgrades, optimising power distribution system assets and demand management.
The study provided the first integrated analysis of context-specific EV multi-fleet expansion in African cities using local mobility data, focusing on Nairobi, Kenya.
Nairobi has about 625,000 privately owned vehicles, 193,000 light-duty commercial vehicles, 11,000 paratransit minivans (matatus) and 600 paratransit buses.
Electric vehicles offer a promising avenue to reducing reliance on imported fuel and carbon-intensive technologies. African nations like Cape Verde, Rwanda, Zimbabwe, South Africa, Egypt, Ghana and Kenya have signalled their commitments to EV adoption through targets and incentives.
In April 2021, Rwanda put forward the Strategic paper on electric mobility adaptation in Rwanda. The paper listed three significant barriers to electric vehicle adoption. They were initial purchase cost, charging infrastructure and concerns regarding range and knowledge gaps.
Meticulous planning and demand-side management are essential. Tackling consumer behavior, handling peak charging demand, and enhancing infrastructure are vital measures for a seamless shift to electric mobility in Nairobi and other African cities.
Kenya reduced excise duty on EV imports from 20 per cent to 10 per cent, aiming for a 5 per cent share of EVs in vehicle imports by 2025.
The draft National E-Mobility Policy, Kenya created March 2024 aimed to include the development of a policy to create an enabling environment for the growth and adoption of electric vehicles in Kenya.
A primary goal of the policy is to encourage local production and assembly of electric vehicles and to improve e-mobility infrastructure to speed up the adoption of EVs.