Alex Engler, Andrew Sarcinello, & Zach Mitchell EDSGN : Intro. to Engineering Design Fall 2010 Client – Driven Design Project The Pennsylvania State University GE TRANSPORTATION NO GRID TELECOM BASE STATION ENERGY STORAGE SYSTEM

TABLE OF CONTENTS Customer Needs & Problem Defintion Statistical Information of Nicaragua Potential Solutions Power Concept Selection Cooling Concept Selection Power Balance Total Energy Equations Power Output Heat Balance Life Cycle Cost Profit Social Implications

WHAT DOES THE CUSTOMER NEED? The telecom company needs a profitable, off-the-grid system to power their “hut” The “hut” is a protection building for the equipment used to support the cell tower

THE PROBLEM We are working off of any main power grid. We must utilize GE’s sodium metal halide batteries We must attempt to make the project economically efficient The equipment in the building requires a 1.2 kW load

INFORMATION What are we Dealing With?

ABOUT THE AREA Area: total: 129,494 sq km water: 9,240 sq km land: 120,254 sq km Elevation extremes: lowest point: 0 m highest point: 2,438 m Temperature averages by elevation Day ( o C)Night ( o C) m –1600 m m 22-24Low of 15 UV Index Average Estimates. WinterSummer

Solar energy can generally be garnered from 6:00 AM – 6:00 PM High points from 11:00 AM - 1:00 PM From December to April, there is the most solar radiation. From May to October, solar radiation drops by about 1/3 average per day. MonthSpeed (m/s) January1.7 February1.8 March2.0 April2.4 May2.1 June1.6 July1.2 August1.6 September1.3 October0.5 Novermber1.3 December0.9 WIND AND SOLAR DATA Average Daily Wind Speeds by MonthSolar Tendencies

WIRUCA, NICARAGUA 48 families All are coffee growers Earn $100 per month per household, $10 disposable income per month No electricity No cell phone service, but they have cell phones for use when traveling Would like to power TV, radio, lights, and fan Mountainous area, hurricane and earthquake danger Community currently pays 1.7 Cordobas/hr for first 25 kW-hr Cell phone service provider - CLARO

POTENTIAL SOLUTIONS How to Power the telecom hut, how to cool it, and should energy be sold?

ENERGY Solar Wind Geothermal Sodium Metal Halide Battery Micro-Hydro Diesel Generator Cooling Air Conditioning Ventilation Heat Pumps No action LISTS OF SOLUTIONS

POWER SOLUTIONS Stability and Reliability

SOLAR ENERGY Current designs of telecom towers use watt solar panels GE produces solar panels for solar electricity GE Energy GEPV-200, Solar Panel, 200 Watt ($1000 +/- $75)

WIND ENERGY Windmill generated energy Although GE is preferable, GE models are on a much larger scale than a single building – or even the entire community. Skystream offers an affordable, appropriate model Skystream 3.7 Grid Tie 1.8kW (Cost = $6,200 +/ $50)

GEOTHERMAL ENERGY Geothermal power plants use heat from the Earth to Mass Produce Electricity. It is very efficient, and could easily utilize the great volcanic activity in the area. Generally used on a large scale, and stations are not manufactured. Cost > $10 million on average

SODIUM METAL HALIDE BATTERY GE is looking to test this innovative design on the telecom expedition Good option for energy storage.

MICRO HYDRO ENERGY Using running water to push turbines and provide power can be very efficient and beneficial. The cost of a system can run from $1,000 - $20,000; although maintenance costs are low. Availability dependent on running water in the area.

DIESEL GENERATOR The diesel generator is not a green or alternative energy source, but it is reliable, and not dependent on outside conditions like terrain and weather. Cost of diesel fuel, $1/liter. About $2.60 per gallon We’d want it to be able to power the hut should all of our alternative energy be out of operation. Option Kohler 20 KW Compact Diesel Generator 40 Gallon Tank Only one year warranty About $17,000

CONCEPT SELECTION

COOLING OPTIONS Fighting the Climate

Would appropriately cool building Not Expensive to Install Requires extra power. GE Options AJCQ06LCC Air Conditioner $400 - $ BTU = 1.76 Kwh AIR CONDITIONING AJCQ06LCC

Working similarly to an air conditioner, heat pumps heat and cool buildings by transferring heat rather than using fuel. Can be economically beneficial, but that would be assuming one uses them for heating and cooling. May not adequately cool in Nicaragua’s warm climate. Option: Fedder’s CH60ACZ1VF Cost $1,100 - $1,400 HEAT PUMPS

If we feel the hut can operate at any reasonable temperature it could be economically efficient to take no action on limiting the temperature within the hut. By maintaining a brisk air flow the and allowing the heat emitted from our materials to exit the building, we may be able to keep the temperature at least somewhat close to that outside If one takes this route one must consider that this could lead to insects getting into the building, which could eventually lead to poor effects on the equipment. NO MECHANICAL COOLING SYSTEM VentilationNo Cooling

CONCEPT SELECTION

We will supply energy to the hut using wind energy from a Skystream windmill, six GE solar panels, and a Kohler Diesel Generator; which will charge GE’s new Sodium Metal Halide Batteries. To deal with the heat, we will be allowing air flow through ventilation, and using low cost/ power fans to keep consistent air flow. We will also try to limit heat given off in the hut with the placement of the electric systems. OUR SOLUTION

POWER BALANCES The balance of power flowing to the hut will change throughout the year. The load needed for the huts will be 1.2 kW plus that required for the lights and fans inside the hut. A safe estimate of the maximum energy needed would be 1.4 kW. Our power sources, at maximum output, could give 24.8 kW Generator – 20 kW Solar Panels – 1.2 Windmill – 2.6 at peak Our goal is to limit the amount of work done by the generator, which will fluctuate in respect to time.

EQUATION OF TOTAL ENERGY GeneratorOutput + SolarOutput + WindOutput + NaMxOut = Load / hr + NaMxCharge [G max * F / hr] + [Panels * S max / hr * E sol ] + [P max (Betz limit) (K)] + NaMxOut = Load / hr + NaMxCharge [ (40kW / Gallon / hr) * F ] + [ 6 * 0.2kW / hr * E sol ] + [ 2.6 kW * 0.59 K ] + NaMxOut = Load / hr + NaMxCharge Where F is fuel in gallons E sol is solar efficiency K is a constant limiting wind output by including inefficiencies in the windmill system.

Solar and wind power also fluctuate by month, so more or less diesel fuel will be required based on our windmill and solar panels’ outputs. The solar power available to us will fluctuate by hour each day, and the wind will be difficult to predict on an hourly basis, but we should have a basic idea of how much diesel fuel we’ll need. EFFICIENCY DIFFERENCES IN POWER OUTPUT From Day to DayFrom Month to Month

Solar Panels Generator Wind January – May Very StrongNot a large part of process Very Strong June – August WeakSomewhat important Strong September - December Grows stronger More importantGrows weaker Solar Panels Generator Batteries 6:00 AM – 9:00 AM Weak but functioning Used in absence of wind Final discharging in cycle 9:00 AM – 3:00 PM Strong, providing majority of energy Shouldn’t be needed. Charges off of wind energy 3:00 PM – 6:00 PM Weak but functioning Used in absence of wind Charges or discharges based on wind 6:00 PM – 6:00 AM Off due to lack of sunlight Maintains electric output w/ batteries Discharges, primary TIME DIFFERENCES IN POWER OUTPUT From Day to DayFrom Month to Month

HEAT BALANCES We know the station will be placed in a mountainous region This should yield a temperature difference of at least 6 o C from that in lower areas. Because the temperature should be averaging F, an expensive cooling system should not be required. We will be putting small fans in the hut as well as proper ventilation to maintain an acceptable temperature. To limit heat produced from equipment, we will place the batteries and generator outside of the hut in an area enclosed with fencing for security.

LIFECYCLES Costs Over Time

Windmill: Turbines should last 20 – 25 years. Maintenance is minimal. Generators: aside from the cost of fuel, filters must be cleaned and oil must be changed regularly. Lifetime is potentially limitless, however. Solar panels: last anywhere from 25 to 50 years. Maintenance is minimal and pertains mainly of removing debris from surface and keeping line of sight clear of shade. Windmill – 5 year limited Generator – 1 year limited Solar Panels – 25 year limited on power output, 5 year limited on materials and workmanship PARTS LIFECYCLES WarrantiesReliability Over Time

ESTIMATED COSTS OVER TIME. The generator will most likely run between hours per day depending on the time of year, so – 730 gallons per year $ $ Based on the three sections of the year shown earlier, we can estimate * 5/ * 3/ * 4/12 = about $ / year Maintenance for panels and windmill should be under $100/year.

SELLING POWER There is interest among many of the villagers to sell extra power produced to the villagers as a business. This would be a very beneficial action for the community However, it would not be economically sound Nearby villages have recently put in solar plants for a power source, and thus would not require power The village consists of 48 families with $10 / month disposable income, and after their cellular coverage expenses, would not be able to make our venture profitable.

POTENTIAL PROFITS Initial expenses are $29,210 for fuel sources plus fencing and ventilation costs. Costs per year should range from $1,100 - $1,200 The telecom company will be selling to a village with 48 families, who average $10/ month disposable income. Approximately $5,760 / year. Bearing unknown interest rates, this project seems to present nothing but a high risk long term investment. If GE is paid 25% of the profits, they will cover expenses after 29,210 / ( 5,760 *.25 – 1,150) = years with our model.

SOCIAL IMPLICATIONS There are great social benefits by having the telecom infrastructure build in Nicaragua, it helps to modernize the community and give them the necessary resources to keep up with vastly growing modern technology. The telecom station will also add job’s to the small community, again giving opportunity for growth. Cell phone usage will go up, allowing for more communication between the civilians leading to a safer and more unified village.

CONCLUSION In conclusion, will we use a heat powered by both solar and wind energy, with a reserve diesel generator used if the wind and solar are in a time of malfunction or low efficiency. The hut will cooled with an installed ventilation system used to draw the hot stagnant air out of the building. We will not sell power to the community due to the lack of economic potential.

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