Over decades, Ghana has been struggling with the generation of electrical power, especially its sustainability.
The associated challenges, either technical and or political are well known. Moreover, predominantly reliant on hydropower, alternative electrical power generation sources such as wind energy, solar energy, bioenergy, etc. have not been tested for implementation on a large scale in Ghana.
The article aims to bring to the attention of the Ghana government and other industry policymakers and actors a new research study on the generation of electrical power from new renewables (solar and wind) on utility-scale and complementary flexible generation from biomass residue and waste, which was conducted at LUT University in Finland.
The scientific research was carried out by MSc. Theophilus Nii Odai Mensah, Dr Ayobami Solomon Oyewo, and Professor Christian Breyer. The study investigated the use of a variety of different biomass-based residue streams from the forest, agriculture, and municipal solid waste to generate electrical power from the sixteen (16) regions of Ghana. In the study, 6 local regions were created out of the sixteen (16) regions in Ghana – such as 1) Eastern-Coastal (GH-EC): Greater Accra, Volta and Oti regions; 2) Western-Coastal (GH-WC): Central, Western, and Western North regions; 3) Central (GH-CEN): Eastern and Ashanti regions; 4) Brong Ahafo (GH-BA): Bono, Ahafo and Bono East regions; 5) Northern Territory (GH-NT): Northern, North East and Savannah regions; and 6) Upper North (GH-UN): Upper East and Upper West regions.
These regions were installed with sufficient local renewable capacity to serve the region using the LUT Energy System Transition model, also known as the LUT model. The LUT model is a linear optimization simulation tool that performs an hourly resolution of the energy system with parameters for an entire year under certain operational constraints and assumptions for the future powered system and demand. Also, the LUT model highlights the role of waste and residue biomass to complement generation from variable renewable energy resources. In addition, system mechanisms applied in the study include electricity generation, power transmission, storage, and energy bridging technologies.
In the research study, six power sector scenarios were developed, among which two main scenarios were adopted for analysis. The two analysed scenarios are the Current Policy Scenario (A Business-as-Usual Scenario) which was modelled based on the current Ghanaian government power plan detailed in the Ghana Energy Commission reports, and the Best Policy Scenario (A fully renewable energy scenario with biomass and hydropower serving as flexible generators besides other storage technologies to balance the variability of new renewables).
It was observed that waste and residues from the forest, agriculture, and municipal solid waste represent a large and currently unused energy source. Municipal solid waste especially has a great potential for expansion, very versatile, and can help to meet energy demands and reduce the accumulation of waste in Ghana. The research further reveals that Ghana’s electric power crisis could be solved with a mix of new renewable energy generators.
The key findings of the research are as follows:
- Renewable energy resources (solar, hydropower, and biomass) can supply the power sector demand of Ghana starting from now.
- Solar PV (Utility scale and prosumers) contributes 76% of the total electricity demand of Ghana by 2050 in the Best Policy Scenario.
- In the Best Policy Scenario, the levelized cost of electricity (LCOE) declines from 48.7 €/MW in 2015 to 36.9 – 46.6 €/MWh by 2050.
- In the Current Policy Scenario (Business as Usual), the levelized cost of electricity (LCOE) increases from 48.7 €/MW in 2015 to 76.4 €/MW by 2050.
- Flexible generation from biomass (forest and crop residues, livestock manure, municipal solid waste, faecal sewage sludge) and hydropower provides system balancing for the power system in the Best Policy Scenario.
- Storage technologies and gas turbine provide day-to-day and seasonal balancing of the transmission grid.
- Local farmers such as cocoa farmers etc. will earn extra revenue from waste and residue sales to local power producers.
- Using residues and waste as fuel for power generation will rid the country of filth and keep the environment clean.
- In terms of regional power generation, the Northern regions of Ghana are the dominant generating hub in a fully renewable power sector due to high solar irradiation in the Northern regions.
- In the Best Policy Scenario, electricity is transmitted from (GH-NT): Northern, North East and Savannah regions; (GH-UN): Upper East and Upper West regions, (GH-EC): Greater Accra, Volta and Oti regions; (GH-CEN): Eastern and Ashanti regions; to complement and satisfy demand in (GH-BA): Bono, Ahafo and Bono East regions and (GH-WC): Central, Western, and Western North regions.
In conclusion, it is claimed that:
- Ghana can generate sustainable electricity from biomass residue and waste to complement generation from new renewables.
- Bioenergy contribution in power systems substantially reduces system cost.
- Bioenergy provides flexibility in hybrid solar PV–battery dominated power system.
- The levelized cost of electricity for 100% RE ranges from 37 – 46.6 €/MWh in 2050.