Project 2Nakuru Cell Tower

The League of Extraordinary EngineersDominick D’Angelo

Scott WhitemanJason Ellis

Problem Statement As a team, our objective is to create a base to

power a cell phone tower in an area where it is not possible to do so, because of limited or nonexistent grid. We plan to use sustainable energy sources along with a diesel generator and a sodium metal halide battery to generate energy, efficiently and cost effectively. Our design will be easy to implement in developing regions that will benefit from the use of this with limited resources.

Introduction

Roughly 300,000 inhabitants Important Educational Center

◦Egerton and Kabarak Universities Economy

◦Agriculture Coffee, wheat, barley, maize and beans

◦Manufacturing◦Tourism

63% cell phones 27% landline access

Research(Nakuru)

Possible Renewable Energies

Wind Technologies◦Average wind speed is not consistently equal

to 12 mphSolar Technologies◦Best option due to solar data, close to

equatorHydroelectric Power◦Not enough moving water to power system◦Lake Nakuru is really the only option

Research

Solar Panels◦Sunflex Grade A 100 W◦PV Size (4 kW)◦Amount Needed (40)◦Cost ($380.00/Unit)

Charge Controller◦Outback Flexmax 80 Charge Controller◦48 VDC System◦Recommended: 4000 W◦Cost ($684.00)

Components

Battery◦Amount (1)◦Type (A1)◦Cost ($7,000)◦Capacity (12.4kwh)

Inverter◦AIMS 5000 Watt power

inverter

◦Volt and Amp meters on front panel to monitor your battery voltage and current usage

Components

Diesel Generator◦Durostar D57200Q (6000 W)◦Run Time (12 Hours)◦Cost ($1000.00)◦Efficiency (20%)

Fuel Tank◦LiquiDynamics Horizontal Fuel Storage Tank◦Capacity (275 gallons)◦Cost ($800.00)

Components

Efuel

Ec

c

Ebatt

Charge Controlle

rRenewable

EnergyEre

Generator

Eg

Batteries

Ec Ed

DC LoadsBTS

DC to AC

Inverter

AC Loads

Ea

c

Einv

Edc

Mode 1: No renewable energy, load drawn from batteries. If batteries empty, use

generator.

Charge Controller

Renewable Energy

Ere

Generator

Eg

Batteries

Ec Ed

EfuelDC

LoadsBTS

DC to AC

Inverter

AC Loads

EacEinv

Edc

Ecc

Ebatt

Mode 2: Renewable energy less than loads, deficit drawn from batteries. If batteries empty, use generator.

Charge Controller

Renewable Energy

Ere

Generator

Eg

Batteries

Ec Ed

EfuelDC

LoadsBTS

DC to AC

Inverter

AC Loads

EacEinv

Edc

Ecc

Ebatt

Mode 3: Renewable energy exceeds loads, excess put into batteries. If batteries full, dump excess.

Battery capacity < 12 kWh will dump excess electricity.

Battery capacity at or > 12 kWh will have no dump, but require more fuel to heat initially

Analysis

0 4 8 12 16 200

100200300400500600700800 Optimal Battery Capacity

4kw system

Battery Capacity (kWh)

Dies

el Fu

el N

eede

d (g

al)

From the 4th-9th year, our hybrid plan is most cost effective

Up until the 4th year the All Diesel is most efficient

After the 9th year, the All Renewable is most effective

Analysis

0 2 4 6 8 10 12 14 16 18 20 22 240

50,000

100,000

150,000

200,000

250,000

300,000

350,000

All DieselAll RenewableInnovation

Analysis

Turbine output

PV output

Generator

Turbin

e outp

ut

PV ou

tput

Genera

torDum

p0

2,0004,0006,0008,000

10,000

Turbine output 0kwhPV output 8,028kwhGenerator output 3,621kwhGenerator fuel 380galGenerator hours 3,233hrDump energy 81kwh

PV Array Size 4kwBattery Capacity (effective) 12kwh

0.31°S and 36.0500°ELocation

SketchUp Model

Roof◦ Slanted for weather◦ Shades roof, thus creating cooler internal

temperature◦ Open space beneath panels creates cooling effect

Ventilation◦ Air flow (Through hut)

Location◦ Connects rural and urban communities

Take-Away