overview of photovoltaic and solar hot water systems...solar water heating (“solar thermal”)...
TRANSCRIPT
![Page 1: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/1.jpg)
Overview of Photovoltaic and
Solar Hot Water SystemsMike Morris
National Center for Appropriate Technology
New England Farm Energy Conference Manchester, NH March 16, 2010
![Page 2: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/2.jpg)
Photovoltaics (“Solar electric”)
solar cell
PV panel or
modulesolar array
• Typical cost $7 per peak watt of DC (direct current) power.
• Add inverter to convert DC to AC (alternating current).
![Page 3: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/3.jpg)
Electricity 101
For example, two, 12-volt panels wired in series runs a 24-volt DC pump.
From Backwoods Solar, www.backwoodssolar.com
• Most panels 12, 24, or 24 volts and 5-200+ watts.
• Amps X Volts = Watts
• Wire in series to increase voltage or in parallel to increase amps.
![Page 4: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/4.jpg)
Siting
• Panels very sensitive to shade.
• Array should be un-shaded
from at least 9 AM - 3 PM.
• Move array to avoid shading,
or oversize array.
![Page 5: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/5.jpg)
Solar mounts
• Pole mounts, roof mounts, trackers (active or passive).
• Mount collectors at an angle equal to your latitude for
year round performance (43 degrees in Manchester).
• For better summer production, decrease tilt angle
• For better winter production, increase tilt angle
![Page 6: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/6.jpg)
Do panels have to face south?
![Page 7: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/7.jpg)
Agricultural Uses
Common
• Electric fence chargers
• Pumping
• Lighting
• Small motors, e.g. fans
• Irrigation system surge valves
Less common
• Wheel line (side roll) sprinkler mover.
• Solar tractors
![Page 8: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/8.jpg)
Solar Pumping
![Page 9: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/9.jpg)
How a Solar Pumping System Works
StorageTank
PV Array
Motor/Power Controller
Pump/Motor
![Page 10: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/10.jpg)
Work with a dealer.
![Page 11: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/11.jpg)
Solar (DC) water pumps: many to choose from
Surface Pumps
Submersible Pumps
Slowpump Suncentric Solar Force Solar Ram
Grundfos SQ Flex Lorentz PS Shurflo 9300 Series
![Page 12: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/12.jpg)
FAQs
• How is the system sized?
• Batteries? Or no batteries?
• Tracking or fixed rack? (Or trailer mount?)
• Reliability? Durability? Vandalism?
• AC or DC pump?
• Diaphragm pump?
• Can I run my sprinkler irrigation system with solar panels?
• How do PV, wind, and (gas, diesel, propane) generator compare?
![Page 13: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/13.jpg)
• 25 cow-calf pairs; 2-3 miles from power
• Two 120-Watt solar panels
• Submersible diaphragm pump (DC)
delivers 1 GPM from 160’ well or 900 GPD
• Cost of solar components: $3,200
• Benefits: Improved reliability and
convenience, compared to gas-powered
generator
Tomlinson Ranch, Gold Creek, MT
![Page 14: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/14.jpg)
Schraudner Ranch, Lavina, MT
• 150 cow-calf pairs; over a mile from power
• Seven 60-Watt solar panels (trailer-mounted)
• Submersible centrifugal pump (AC) delivers
6.5 GPM from 60’ well or 3,600-4,000 GPD.
• Cost of solar components: $10,650
• Benefits: Increased forage base to extend
grazing season; reduced pressure on riparian
area; water source during drought.
![Page 15: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/15.jpg)
Ueland Ranch, Anaconda, MT
• Cost of solar components: $7,700
• Primary benefits: Fisheries benefits from
reduced pressure on riparian areas, drinking
water for cattle at feeding area.
• 500 cow-calf pairs; ½ mile from power
• Twelve 64-Watt solar panels
• Submersible centrifugal pump (DC) delivers 17 GPM (Feb. through
April) from 50’ well.
![Page 16: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/16.jpg)
Sauerbier Ranch, Alder, MT
• Cost of solar components: $24,500
• Primary benefits: Increased forage base,
increased herd size, fisheries benefits for rare
population of West Slope cutthroat trout.
• 350 cow-calf pairs; >5 miles from power
• 24 120-Watt solar panels on two tracking racks
• Surface piston pump (DC) delivers 11 GPM or 7,500 GPD from stream.
![Page 17: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/17.jpg)
Sauerbier Ranch, cont’d
• Pumps surface water over two miles
to the top of a ridge, against over 400
feet of head.
• Fills 8,000 gallon storage tank and
six 1,000+ gallon stock tanks
![Page 18: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/18.jpg)
Solar Water Heating (“Solar thermal”)
• One of the most cost-effective uses of solar energy.
• Currently eligible for 30% federal tax credit.
• Image problem dating back to the 1980s; modern equipment
works very well.
• Suitable for any farming operation that uses a lot of hot water.
• Dairies should probably do heat recovery on refrigeration
system and/or heat exchange on milk first.
• Works well with radiant floor heating.
![Page 19: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/19.jpg)
The basic idea (with many variations)
From www.builditsolar.com
![Page 20: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/20.jpg)
Flat Plate Collector
• Durable copper, aluminum and glass design
• Sheds snow well because collectors get warm
SC
So
lar,
In
c.
![Page 21: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/21.jpg)
Flat Plate Collector
Drawing courtesy of SC Solar, Inc.
![Page 22: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/22.jpg)
Evacuated Tube Collector
• New technology; most expensive.
• Highest temperature output.
• Do not shed snow & ice.
SC
So
lar,
In
c.
![Page 23: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/23.jpg)
Transfer Fluids
• Propylene Glycol- Non-toxic
• Ethylene Glycol- Toxic
• Hydrocarbon Oil (bray oil)
• Synthetic Oils
• Distilled Water
• De-mineralized Water
• Potable Water
![Page 24: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/24.jpg)
Active vs. Passive
• Active systems use a pump to circulate fluid
• Passive systems rely on tendency of hot water to
rise.
Direct (“open loop”) vs. Indirect (“closed loop”)
• Direct systems use potable water in the solar
collectors
• Indirect systems use water or glycol in a separate
loop from the potable water.
System Types
![Page 25: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/25.jpg)
Passive Batch System
![Page 26: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/26.jpg)
Active Indirect System (“Drainback”)
System controller measures
temperature difference
between sensors.
ON 8-20 difference
OFF 3-5 difference
![Page 27: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/27.jpg)
Solar Water-Heating for Greenhouses
Design issues
• Freeze protection a must.
• No toxic fluids around crops or leaking into soil.
• Need to dump heat (or disable) in summer months, if
sized for winter needs.
• Backup heating system desirable.
• Tubing can be buried or above-ground, depending on
use of greenhouse.
![Page 28: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/28.jpg)
Cherry Research Farm, Goldsboro, NC
• Cost $8,000; $3,900 after NC
and federal incentives.
• 250 gallon water “drain down”
system
• Cut propane costs from
$3,000 to $1,000 per year.
![Page 29: Overview of Photovoltaic and Solar Hot Water Systems...Solar Water Heating (“Solar thermal”) •One of the most cost-effective uses of solar energy. •Currently eligible for 30%](https://reader033.vdocument.in/reader033/viewer/2022060304/5f092d0b7e708231d4259680/html5/thumbnails/29.jpg)
Thank you for your attention!
NCAT: www.ncat.org or 1-800-ASK-NCAT
ATTRA: www.attra.org or 1-800-346-9140
Mike Morris: [email protected] or 919-251-9680
Farm Energy resources: www.attra.org/energy