Page 24 - Engineering in Kenya Mag

DISCUSSION
The current effective installed (grid connected) electricity capacity in Kenya is 2,651MW, with peak demand of 1,912MW. Demand has been rising at a calculated rate of 3.6 percent every year mainly due to the expansion of grid connections for public facilities and surrounding households.
Energy figures point to significant opportunities to make Kenya’s industries and buildings more energy efficient through improving demand-side (end-user) practices and reducing system losses. Kenya’s entire building stock as of 2018 was estimated at approximately 37 million m2 and the figure is expected to grow to 47 million m2 by 2025. Significant growth is anticipated to come from the residential, commercial and hospitality space. Overall building sector energy consumption was 11.52 MT of oil equivalent in 2015, representing approximately 73% of total final energy consumption (IEA 2015). Ongoing
economic growth, supply constraints driven by increasing energy access objectives, and the prevalence of the building sector in national energy use data all point to the critical nature of building energy efficiency to overall energy security and economic productivity objectives in Kenya, as well as to addressing climate change obligations.
The Internet of Things (IoT) provides equipment and appliances with a gateway for communicating and making decisions autonomously, without human intervention. The sensors used could be pressure, light, temperature, proximity or motion sensors. Wireless communication systems play a crucial role in activating IoT. They connect the sensor devices to IoT gateways and perform end-to- end data communications between these elements of IoT. Wireless systems are developed based on different wireless standards and the use of each one depends on the requirement of the application such as communication range, bandwidth and power consumption requirements.
Table 1: Comparison between different wireless technologies
Technology
Range km
Data Rate Security Installation
Power Usage
Security
Installation Cost
Example Application
LoRa
<50
0.3–38.4 kbps
Very Low
High
Low
Smart Lighting
NB-IoT
<50
<100
High
High
Low
Smart grid communication
LTE-M
<200
0.2–1 Mbps
Low
High
Moderate
Smart Meter
Sigfox
<50
100 bps
Low
High
Moderate
Smart Electric Plugs
Weightless
<5
100 kbps
Low
High
Low
Smart Meter
Bluetooth
<50
1Mbps
Low
High
Low
Smart home appliances
Zigbee
<100
250Kbps
Very Low
Low
Low
Smart metering in renewable energies
Satellite
Very Long
100kbps
High
High
Costly
Solar & windpower plants
The use of smart thermostats in buildings to maximise energy efficiency by adjusting the temperature. They can be used to control fans, room heaters and also in smart refrigerators to automatically adjust their temperatures and monitor power usage. One can also be pre-emptively notified when maintenance will soon be needed. The IoT devices connect through the Internet where each device has a unique IP address. The remote monitoring and control are done through cloud-based control systems.
Light-Emitting Diode (LED) luminaires can be used as light sensors in smart buildings to control lighting. Energy smart meters and smart building management systems can be implemented to help in energy consumption forecasting. Sensors can be embedded in all electric devices for example TVs, air-conditioners, humidifiers to monitor and regulate their power use. The ultimate goal is to progressively automate our buildings while increasing the efficiency of processes.
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Engineering in Kenya Magazine Issue 002