Using atmospheric pressure tendency to optimise battery
charging in o-grid hybrid wind-diesel systems for
telecoms
Phelan, Shane
(2014)
Using atmospheric pressure tendency to optimise battery
charging in o-grid hybrid wind-diesel systems for
telecoms.
PhD thesis, Dublin City University.
Off grid telecom base stations in developing nations are powered by diesel generators. They are typically oversized and run at a fraction of their rated load for most of their lifetime. Operating these generators at partial load is
inefficient and over time physically damages the engine. A hybrid configuration,which is the combination of multiple energy sources, uses a battery bank which powers the telecoms load for a portion of the time. The generator only
operates when the battery bank needs to be charged. Adding a wind turbine further reduces the generator run hours and saves fuel. The generator is oblivious to the current wind conditions which lead to simultaneous generator-wind
power production. As the batteries become charged by the generator, the wind turbine controller is forced to dump surplus power as heat through a resistive load.
This dissertation details how the relationship between barometric pressure and wind speed can be used to add an additional layer of sophistication to the battery
charger. A numerical model of the system is developed to test the different battery charging configurations. This work demonstrates that if the battery charger is aware of upcoming wind conditions it will provide modest fuel savings
and reduce generator run hours in small scale hybrid energy systems. The contribution from this work provides insight into the power being wasted in small scale hybrid systems with storage and how they can operate more efficiently when the charging mechanism is aware of upcoming wind conditions.
The system will operate more efficiently if the diesel generator is disengaged during periods of moderate to high wind power production. The methodology proposed in this dissertation ensures that this is the case, especially during periods of high wind power production.
Metadata
Item Type:
Thesis (PhD)
Date of Award:
March 2014
Refereed:
No
Supervisor(s):
Stephen, Daniels and McArdle, Conor
Uncontrolled Keywords:
Off-grid power generation; Efficiency; Optimisation