Oberbauer/ITEX Solar Power Systems

Transcription

1 Oberbauer/ITEX Solar Power Systems Set-Up, Operation and Maintenance Manual System #1 at Imnavait Creek System Description: These solar power systems are designed to provide the ITEX project with a reliable source of AC and DC electricity without the noise, fumes, fueling and maintenance requirements of an engine generator. The systems are intended for summer use only, but the ruggedized components are capable of over-wintering in the field. Each system has a maximum solar generation capacity of 260 Watts, which in these high latitude locations should result in about 1.5 kwh energy production each day. The two 12 volt, 106 amp hour batteries result in an energy storage capacity of approximately 2.5 kw hours. As such, they should provide more than adequate power capacity for this project, even during periods of inclement weather. The systems are easily expandable in terms of both power production and energy storage by 50% should the need arise.

2 Both AC and DC power are exported from the power system to a distribution box on the end of a 25 umbilical, providing the project with some flexibility in placement, while ensuring that any wind vortices or additional snow accumulation caused by the solar array is kept out of the study area. Power output to the experiment is limited to 300 Watts continuous on the AC side at 115 volts. The inverter is capable of surging to 600 Watts for limited times (~10 minutes) which is critical for reactive loads such as the tram motor. The sealed inverter provides a very high power quality with a true sine wave output. Power on the DC side is limited to 120 Watts by the 10 amp breaker. This should be far more than what is required by the data logger and other small DC loads. Power distribution panel The largely plug and play system can be assembled in the field in about four hours by two individuals familiar with the set-up. For inexperienced folks it will obviously take longer. Please follow the set-up instructions found later in this manual. The ballasted design is self-supporting, facilitating a quick deployment. Guy lines should be added for very windy areas where additional support may be desirable. These systems have been optimized for summer use in polar environments, and are not intended for year-round power availability. Year-round power stations for data acquisition and/or data transmission are also available.

3 Main Power System Specifications: 1ea) IRP insulated, weather resistant enclosure, approximately R-14 2ea) 130 Watt Kyocera, KC130 PV panels 2ea) Concorde Sun-Xtender 106 amp hour, 12 volt, AGM batteries. (2,586 Watt hours of energy storage) 1ea) Morningstar 30 Amp solar charge controller with integral DC load control 1ea) Morningstar 300 Watt Sure-Sine inverter (can surge to 600 Watts) 1ea) 115VAC/15 amp duplex electrical outlet Circuit protection for safety and reliability: - Outback AC/DC type breakers - Blue Sea Systems ST fuse block, for ATO/ATC blade type fuses The system is capable of producing a maximum of 300 watts of 115VAC power continuously for up to five hours without overdrawing the batteries, greater if there is renewable energy input. The system is also capable of supplying 12VDC power, for direct charging of most laptop computers (adaptor required) and powering other 12 volt equipment. AC and DC power is available both inside the electronics enclosure, as well as at the remote distribution center. The interior of the electronics enclosure allows room for some storage of science gear at the sites. Power Distribution Panel: A power distribution panel is set up at the end of 25 of armored, liquid tight, flexible conduit. This allows for the main power system to be located a reasonable distance away so as to avoid accumulating large amounts of non-representative snow in immediate proximity to the experiment site. Both 115 Vac and 12 Vdc are available. DC power can be accessed via a 6-position fuse block. AC can be accessed either at the internal breaker or at the weather resistant, in-service duplex receptacle below the enclosure. All components are wired using specialized low temperature rated conductors. The Morningstar components are rated for storage to -50C, allowing the systems to over-winter in the field. Set-Up: Setting up the Polar Pod for operation is relatively simple, and can be done by two people in about four hours time. It is possible for one person to set the unit up in the field, but due to the weight of the battery box and other components, it is recommended to have a minimum of two people on hand.

4 1. Develop the overall plan for setting the system up. The solar panel (PV) must face south (in the northern hemisphere) and be unobstructed by anything that might shade the panel. 2. Set up the PV frame first. 3. Remove the frame components from the shipping crates. 4. The frame components are all marked. Lay them out on the ground and loosely connect together using the supplied hardware. Do not tighten any bolts until every component is loosely in place. 5. Orient the frame with the PV panels facing within 10 degrees of true south. Remember that magnetic declination in the high latitudes can be extreme. A GPS or even visual orientation can be a better method than a magnetic compass. 6. Set the box in place within the bottom frame cradle. Typically, the ballast of the box is adequate to hold the frame in place. For extremely windy locations, guy cables are run out to appropriate anchors. 7. Pound in the ground rod provided within 3 of the battery/electronics box. Run the #4 green/yellow cable between the ground rod (secured with acorn nut) to the aluminum lug on the exterior of the frame marked Earth Ground. 8. Connect the two solar panels together in parallel (+/+ and -/-) using the pre-made interconnect cable provided. 9. Bring the pre-made solar cable into the enclosure, attaching positive (PV+/red) to the positive side of the distribution block. Connect PV negative (-/black) to the negative side of the distribution block. 10. Turn on the breaker marked Battery. This activates the PV charge controller, which should now read >12.3 Vdc as it automatically scrolls through the display. 11. Turn on the breaker on the power panel labeled PV. The charge controller display should now read out amps going in to the batteries, as well as show a gradually increasing battery voltage. 12. Set the angle on the PV panel to be as perpendicular to the angle of the sun as possible. This is called the angle of incidence. The more perpendicular to the sun, the higher the power output of the panel. This angle may need to be adjusted a few times over the course of the polar summer. 13. Check the voltage on the LCD display over a period of a few hours. If the sun is out, the voltage should slowly begin to rise. A fully topped off 12 volt battery under charge will read around 14.3 volts. Bear in mind that it will take many hours in full sun to reach this value. 14. The power supply can be used at this time. Switch on the 50 amp inverter breaker to make 115 Vac available at the pigtail outlet. Switch on the DC breaker to the fuse block if 12 Vdc is required. 15. Install guy cables on the main A-frame and run to appropriate earth anchors if required. 16. Set up the remote distribution frame and panel in the chosen location. 17. Run the 25 section of armored, liquid tite conduit between the main power box and the distribution panel. 18. At this point, all breakers should be in the up/on position. Monitor the battery voltage carefully over the first few days to ensure that everything is operating appropriately.

5 Maintenance: Unlike an engine generator, there is really very little maintenance to be done. There is no fuel to add, no oil to change, no spark plugs, no concerns about inclement weather. In fact, this system runs on environmentally derived power sources or weather. If it is a nice, sunny day, the PV will provide ample power. There is adequate energy storage in the batteries to last through several days of overcast weather while continuing normal operations. If the glass on the PV panel becomes obscured, it will reduce output, so keep debris and snow off of it. Moisture and electronics don t mix.keep moisture out of the enclosure to the greatest extent possible. If moisture does get in, get the majority of it out by absorbing it with a rag, sponge, paper towel, etc. Then on a warm, sunny day, open it up for evaporation to do the rest. If the unit is set up on snow cover, it will ultimately end up sitting on a snow pedestal, as the snow all around it melts away. The solution is simply to move it to a new spot before it falls over. As mentioned above, the battery voltage should be checked periodically to ensure that it is charging adequately. With no load (nothing but the PV panels plugged in), voltages up to 14.5VDC are normal. Long periods of reduced sunlight (days of overcast) can lead to lower battery voltage. If voltage drops below 11.8VDC, it may be necessary to reduce loads or make efforts to track the sun over the course of the day. If voltage falls too low, the inverter will turn itself off until voltage recovers. Once voltage returns to normal, power once again becomes available. Winter Storage: Turn off all breakers except for the ones marked PV and Battery. This leaves the battery and PV panels connected through the charge controller, ensuring that the batteries stay healthy for the winter. Disassembly: Turn off all of the breakers. Unplug all cords. Reverse order of assembly. Please take care to re-pack components carefully into their respective shipping crates to ensure safe transport and long service life. Carpe Diem!

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8 Overlooking Imnavait Creek. Brooks Range/ANWR in background.