Energy

Coconut Wastes as Bioresource for Sustainable Energy: Quantifying Wastes, Calorific Values and Emissions in Ghana

gkkayetor — Mon, 11 Jan 2021 16:41:40 +0000

Coconut Wastes as Bioresource for Sustainable Energy: Quantifying Wastes, Calorific Values and Emissions in Ghana gkkayetor Mon, 01/11/2021 - 16:41 Prof. George Yaw Obeng Dr. Charles Sekyere

Coconut husks with the shells attached are potential bioenergy resources for fuel-constrained communities in Ghana. In spite of their energy potential, coconut husks and shells are thrown away or burned raw resulting in poor sanitation and environmental pollution. This study focuses on quantifying the waste proportions, calorific values and pollutant emissions from the burning of raw uncharred and charred coconut wastes in Ghana. Fifty fresh coconuts were randomly sampled, fresh coconut waste samples were sun-dried up to 18 days, and a top-lit updraft biochar unit was used to produce biochar for the study. The heat contents of the coconut waste samples and emissions were determined. From the results, 62–65% of the whole coconut fruit can be generated as wastes. The calorific value of charred coconut wastes was 42% higher than the uncharred coconut wastes. PM2.5 and CO emissions were higher than the WHO 24 h air quality guidelines (AQG) value at 25 °C, 1 atmosphere, but the CO concentrations met the WHO standards based on exposure time of 15 min to 8 h. Thus, to effectively utilise coconut wastes as sustainable bioresource-based fuel in Ghana, there is the need to switch from open burning to biocharing in a controlled system to maximise the calorific value and minimise smoke emissions.

Energies | Free Full-Text | Coconut Wastes as Bioresource for Sustainable Energy: Quantifying Wastes, Calorific Values and Emissions in Ghana (mdpi.com)

Towards zero vehicle emissions in Africa: A case study of Ghana

gkkayetor — Mon, 11 Jan 2021 16:22:56 +0000

Towards zero vehicle emissions in Africa: A case study of Ghana gkkayetor Mon, 01/11/2021 - 16:22 Dr. Godwin Ayetor Prof. David Ato Quansah Dr. Eunice Adjei Akyereko

This paper reviews vehicle standards in Ghana and other parts of Africa. The paper also considers the cost of ownership of electric vehicles in Ghana. Tesla Model 3, Tesla Model S, Nissan Leaf and Toyota Prius are compared to Toyota Corolla. The parameters considered are initial cost, maintenance cost (spare parts and labour), fuel cost, and availability of skilled labour. Considering Ghana's energy mix, a conventional vehicle will emit 3.35 times more CO2 emissions compared with an electric vehicle. The results show that while there are 30% savings on cost per mile for Toyota Prius it cost at least 13.5% more to own an electric vehicle compared to Toyota Corolla. The Ghana government's tax incentive for removing import levy will only reduce the cost per mile by 2.5%. Ghana's energy surplus of 98.59 GWh is enough to charge at least 1.5 million electric vehicles. But a huge skills gap in electric vehicle maintenance, non-availability of spare parts, charging infrastructure and the initial price of electric cars are the main challenges to overcome to boost electric vehicle penetration in Ghana and other countries in Africa.

https://www.sciencedirect.com/science/article/pii/S030142152030344X

Integrated system efficiency in reducing redundancy and promoting residential renewable energy in countries without net-metering: A case study of a SHS in Ghana

gkkayetor — Mon, 11 Jan 2021 16:19:22 +0000

Integrated system efficiency in reducing redundancy and promoting residential renewable energy in countries without net-metering: A case study of a SHS in Ghana gkkayetor Mon, 01/11/2021 - 16:19 Dr. Richard Opoku

One of the key factors affecting progress of renewable energy (RE) in the residential sector in Africa is the unavailability of net-metering systems in many of its member-state countries. Huge battery storage would have to be put in place by individual households owning solar home systems (SHS) to store energy for early morning and night-time use, making the systems not cost-competitive. In this study, a new concept based on “integrated system efficiency (ISE)” has been developed to maximize direct use of electricity from SHS without net-metering. In a case study, real-time power consumption and solar PV electricity generation were monitored for an installed SHS in Ghana. The result showed that, in the absence of net-metering system, sustainable hybrid SHS can be realized if high consumption electrical loads comprising refrigeration systems, water pumping, and washing machines are shifted to daytime use, using ISE. The significant contribution of this study is that, for SHS without net-metering, a new performance parameter called “solar system redundancy factor” is identified as more appropriate indicator for measuring the actual usage of the PV electricity generation. Using the ISE concept developed in this study, the redundancy factor was minimized from 63.2% to 39.8% for the SHS.

https://www.sciencedirect.com/science/article/pii/S0960148120304316

Energy efficiency and cost saving opportunities in public and commercial buildings in developing countries : The case of air-conditioners in Ghana

gkkayetor — Mon, 11 Jan 2021 16:12:15 +0000

Energy efficiency and cost saving opportunities in public and commercial buildings in developing countries : The case of air-conditioners in Ghana gkkayetor Mon, 01/11/2021 - 16:12 Dr. Richard Opoku

Available data and market surveys conducted in Ghana have shown that 60e80% of electricity consumed in offices of public and commercial buildings is used to run air-conditioners to provide indoor thermal comfort for productive office work. Electricity consumptions of these air-conditioners are relatively high and are in the range of 3000e5400 kWh/yr per air-conditioner depending on the brand and the cooling capacity. Low energy efficiency rating of the air-conditioners is a major contributing factor to their high electricity consumption. This present work has conducted studies on the energy efficiency of air-conditioners used in the offices of public and commercial buildings in Ghana. Technical data from a national survey conducted on air conditioning equipment used in the country was used for this study. In addition, a power quality clamp meter was used to monitor the actual power consumptions of stratified samples of the conventional air-conditioners in the offices, as well as that of an inverter air-conditioner installed in an office.
The results from this study show that over 85% of air-conditioners used in Ghana exist in the lowest energy efficiency ratio category (1-star) and the remaining percentages are in the next lower categories (2 and 3-stars). It has been determined that enforcing energy efficiency regulations to shift the air conditioner market in Ghana into the higher energy efficiency ratio (EER) categories has huge benefits for the country. For instance, there are annual electricity savings potential of 260 GWh and 1770 GWh respectively for the year 2020 and 2030 using inverter air-conditioners which have higher energy efficiency rating (4-star equivalent) compared to the current lower EER air-conditioners in the country. It is also determined that if Ghana continues to follow business as usual with low EER air-conditioners, it will need to install electricity generation capacity of about 480MW by 2030 to handle influx of low energy efficient air-conditioners alone. Financial analysis has also revealed that there is opportunity for electricity consumption cost savings of about US$ 1.96 billion from the year 2018e2030 with higher EER air-conditioners (4-star) being installed in the country compared to the current low EER air-conditioners.

https://www.sciencedirect.com/science/article/pii/S0959652619315872

Mechanical Engineering Spearheads Innovative Research in Energy Efficiency and Renewables in Buildings

jkgbeve — Mon, 24 Dec 2018 10:37:36 +0000

Mechanical Engineering Spearheads Innovative Research in Energy Efficiency and Renewables in Buildings i jkgbeve Mon, 12/24/2018 - 10:37

The Department of Mechanical Engineering at the College of Engineering of the Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, for the past several years has been conducting research in energy including renewable energy.

In more recent times, the research focus has been on energy efficiency in buildings and powering these buildings with renewables. This research drive is conducted in collaboration with both local and international partners including the Ghana Energy Commission, DANIDA, the Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ), etc. To train the next generation of energy efficiency innovators, the Department conducts these research with strong involvement of students at various levels including undergraduate and postgraduate students (MSc and PhDs).

One of the success stories through this research, with support from DANIDA, is the fabrication of a grid-tied solar powered air-conditioning system used in one of the offices at the Air-conditioning and Refrigeration Laboratory at the Department. The system depends on solar in the daytime and on grid electricity in the night time.

Also, the Department has developed an innovative sandcrete-sawdust composite building material that is able to reduce wall transmission load in buildings. Preliminary investigation has shown that use of the composite material in buildings will be able to reduce electricity consumption of air-conditioners by about 25-30%, compared to conventional buildings materials used in Ghana.

As part of its ENERGY EFFICIENCY RESEARCH AGENDA 2020, the Department intends to rollout some of the key findings emanating from their research through support-based pilot projects in public and commercial buildings in Ghana that will be able to save substantial amount of electricity in these buildings. In particular, the Department is collaborating with the Millennium Development Authority (MiDA) to support KNUST to undertake energy efficiency project to reduce its electricity consumption and also diversify its energy sources to include solar energy.

Project coordinators: Prof. George Yaw Obeng & Dr. Richard Opoku