Sustainable Energy Infrastructure
One Community’s energy infrastructure is just one aspect of our For The Highest Good of All blueprints for self-sufficient and self-propagating teacher/demonstration communities, villages, and cities strategy to be built around the world. Just as we will are open source project-launch blueprinting a diversity of eco building methodologies and alternative food production options, so too will we showcase and open source and free-share the setup and implementation of a diversity of alternative energy methodologies ranging from traditional generators to solar, wind, and newer technologies as they become available.
RELATED PAGES
INFRASTRUCTURE OVERVIEW ● SOLUTION BASED THINKING ● OPEN SOURCE PURPOSE
WAYS TO CONTRIBUTE TO EVOLVING THIS SUSTAINABILITY COMPONENT WITH US
SUGGESTIONS ● CONSULTANTS ● PIONEERS
CONSULTANTS ON OUR SUSTAINABLE ENERGY INFRASTRUCTURE
Doug Pratt: Solar Systems Design Engineer
JP Novak: Power Backup Systems Designer at Native Construction and Renewables
Lorenzo Zjalarre: Physicist and Energy Efficiency Expert
SUSTAINABLE ENERGY SYSTEMS OPEN SOURCE PORTAL
We are beginning with open source project-launch blueprinting a 283 kWh photovoltaic (PV) solar system easily capable of powering a small village. As we continue to research and develop the One Community infrastructure we will be exploring increasingly effective and affordable ways to expand this system. As we do so, we will use this page as the portal to all the open source and free-shared project-launch blueprinting details related to this and the on-going development and evolution of the One Community sustainable energy infrastructure component including:
● Design plans
● Detailed materials list and providers
● Detailed cost and maintenance analysis
● Detailed equipment and tools needed list
● Detailed build-time and setup time analysis for each evolution
● On-going maintenance and upkeep details per our on-going experience
● Instructions and videos for duplication, what to watch out for, how to expand your system
● List of everyone who helped us design and build this so they can be contacted to help others change it
INITIAL ENERGY INFRASTRUCTURE COST ANALYSIS
One Community’s off-grid energy infrastructure to supply the SEGO Center City Hub, Pod 1, and aquaponics sustainable food infrastructure will be a 283 kWh photovoltaic solar power system. We have chosen this as our initial energy infrastructure because these systems are dependable and capable of being shipped and duplicated anywhere in the world. We will use bio-diesel generators as back-ups to this PV system and intend to explore, demonstrate, and open source share whenever possible a diversity of additional energy options (see below) for expansion of our energy infrastructure for Pod 2 and beyond.
The following price quote is current as of January 2013.
| Item | Description | Qty. | Unit Price | Ext. Amount |
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PV-based power system designed to deliver approximately 283 kWh/day under average December sun conditions at the One Community property |
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| 110-0053 | Suniva, 250W PV Module, TE F-M0 PV Wire, 46mm Clear Frame, 60 Cell Mono, 15A Fuse, 223.2W PTC, OPT250-60-4-100 *** Wire PV array as 32 series strings of 12 modules each. 2 strings per SB6000US inverter. *** ProSolar ground racking for 96 columns of 4 modules each detailed below. 1.5” steel pipe to be supplied locally. |
384 | 266.00 | 102,144.00 |
| 210-0600 | ProSolar, Support Rail, 3” Extra Deep support rail, 164”, Qty. 1, R-164XD |
192 | 35.03 | 6,725.76 |
| 240-0178 | ProSolar, U-Bolt Assembly, Clear, Qty. 1, A-UAS-1S |
384 | 6.22 | 2,388.48 |
| 211-0200 | ProSolar, End Cap, 3”, Clear Anodized, XDeep Channel, Qty. 1, A-EZECAPXD-1 |
384 | 1.62 | 622.08 |
| 260-0029 | ProSolar, End Clamp 1.810” (45.9mm-46.4mm), Clear, Qty. 1, C1810EC-1 |
390 | 2.01 | 783.90 |
| 260-0046 | ProSolar, Mid Clamp 2.50” (42mm-48mm), Clear, Qty. 1, C250IMC-1 |
580 | 2.01 | 1,165.80 |
| 590-0011 | Wiley Electronics, WEEB Grounding Lug with 1/4” mounting hardware, WEEB-LUG-6.7 |
195 | 4.34 | 846.30 |
| 590-0012 | Wiley Electronics, WEEB Grounding clip for ProSolar, WEEB-PMC |
490 | 0.80 | 392.00 |
| 550-0009 | Die Co, Cable Clips, Galvanized, Qty. 100, DCS-897-M565 Clip | 12 | 26.07 | 312.84 |
| 550-0036 | USE-2 Cable, 10AWG, 7-strand 600VDC, black, 3000’ spool, 10-7-3000-sgl |
1 | 875.64 | 875.64 |
| 550-0126 | TE Connectivity, SolarLok Plug with Machined Pin, 4.5-6mm OD,10AWG, USE-2, Female Negative (Blue), 6-1394462-4 |
50 | 2.04 | 102.00 |
| 550-0127 | TE Connectivity, SolarLok Plug with Machined Pin, 4.5-6mm OD,10AWG, USE-2, Male Neutral, 7-1394461-5 |
50 | 2.04 | 102.00 |
| 550-0363 | Rennsteig, Crimping Pliers, TE (TE Solarlok), with Dies & Locator, Solar AWG 14/12/10, R624 817 3 1 |
1 | 323.90 | 323.90 |
| 310-0393 | SMA, Sunny Boy 6000TLUS 1-Ph Grid Tied Inverter, 6000W, 208/240VAC, 60Hz, DC Discon, 6 Dual Fused Input Combiner, 1 MPPT, 10 Yr Warr, Ungrounded, Arc-Fault Protection, SB6000TLUS-12 |
16 | 2,796.07 | 44,737.12 |
| 570-0028 | SMA, Communication Card, RS-485 Module, SB RS 485-N | 16 | 104.50 | 1,672.00 |
| 500-0114 | SMA, Multicluster Box, 3-Ph for 12 x 120V, 60 Hz, SI5048U, add MC-PB, UL listed off-grid only, MCB-12U |
1 | 14,294.09 | 14,294.09 |
| 500-0116 | SMA, Multicluster Communications (Piggy-Back) Card, One for each SI Cluster Master, MC-PB |
4 | 230.20 | 920.80 |
| 311-0040 | SMA, Sunny Island 6048 battery inverter, 5750W, 120VAC, 60Hz, 56A Transfer, 48VDC, Sinewave, 100A Charger, 5 Yr Warranty, with BTS, SI6048-US-10 |
12 | 4,101.54 | 49,218.48 |
| 500-0020 | Outback, FlexWare 500 DC Enclosure with Ground & Pos Bus, 500A DC Shunt, FW-BBUS, for 1 to 2 Inverters, FW500-DC |
4 | 223.62 | 894.48 |
| 530-0026 | Midnite Solar, Circuit Breaker, Panel Mount, 175A, 125VDC, 1-Pole, 1.5” Wide, 3/8” Studs, MNEDC175 |
12 | 77.12 | 925.44 |
| 430-0023 | Cobra, Battery Cable, 2/0 AWG, Black, 600V, THW, by the foot, Code Approved, 2/0-X-FLEX-B |
100 | 5.21 | 521.00 |
| 440-0025 | Quick Cable, Magna Lug, 2/0 Straight Lug, 3/8”, Qty. 1, 6420-F |
24 | 2.93 | 70.32 |
| 440-0066 | Power Panel Component, Quick Cable Heat Shrink, 4-2/0AWG, Red, Qty. 1, UL Listed, 5614-001R |
12 | 1.00 | 12.00 |
| 440-0067 | Power Panel Component, Quick Cable Heat Shrink, 4-2/0AWG, Black, Qty. 1, UL Listed, 5613-051B |
12 | 1.00 | 12.00 |
| 430-0025 | Cobra, Battery Cable, 4/0 AWG, Black, 600V, THW, by the foot, Code Approved, 4/0-X-FLEX-B |
160 | 8.00 | 1,280.00 |
| 440-0026 | Quick Cable, Magna Lug, 4/0 Straight Lug, 3/8”, Qty, 1, 6440-F |
32 | 4.47 | 143.04 |
| 440-0083 | Quick Cable, Heat Shrink, 1/0-250MCM, Black, Qty. 1, UL Listed, 5615-051B |
16 | 1.19 | 19.04 |
| 440-0084 | Quick Cable, Heat Shrink, 1/0-250MCM, Red, Qty. 1, UL Listed, 5616-051R |
16 | 1.19 | 19.04 |
| 440-0178 | MK Battery, Unigy II, 4V, 2 Cell Module, 2424Ah @ 24hr, Interlock, 2AVR125-33 IL *** Sealed battery pack above to be configured w/ two 48v strings per cluster (there’s 4 clusters). Will deliver approx. 2.5 days of power use. Life expectancy is 15-20 years. |
96 | 2,166.31 | 207,965.76 |
| Subtotal | 439,439.31 |
| Estimated Shipping Cost | 10,987.23 |
| Tax Total | 37,357.62 |
| Total | 487,833.16 |
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As part of our self-sufficient and self-propagating teacher/demonstration communities, villages, and cities strategy our goal is to make duplication of a solar array like this as easy as possible through:
- Establishing relationships with companies willing to A) offer discounts to consumers for new-business direct referrals through us and B) affordably drop-ship these orders anywhere in the world
- Open source sharing videos and tutorials for the building and setup process
- Streamlining the process as much as possible for people by expanding existing sustainability networks to create complete package ordering options wherever they don’t already exist
HOW WE ARRIVED AT THE ABOVE SYSTEM
Electric power requirements (see below) have been estimated by JP Novak of Build Native.com. The above system was then designed by Doug Pratt applying his 27 years of solar design and installation experience to confirm these estimates (below) seem reasonable. Estimating how people will use power in advance is always a guessing game. Humans are nothing if not variable and we anticipate that this system will almost certainly require some fine-tuning. We also anticipate that our group will learn from experience and probably become more energy aware and conservative with time. To help us gather data and fine-tune our process as part of our open source sharing, we will be using simple metering on all pods and the aquaponics systems. By doing this we will be able to identify “energy hogs” and share this data, our solutions, and the objective energy saving results of our solutions.
The total electrical use for Pod 1, aquaponics, and the SEGO Center City Hub, on a yearly average, is estimated to be 282.5 kWh per day. This is the figure used to size the solar electric system. In addition, all the AC appliances that were likely to be on simultaneously were totaled up. These included a percentage of lights, laptops, microwaves in the pods, along with all the aquaponics hardware, and most of the kitchen and community center lighting and hardware (including the hot tub). This max AC surge was about 76 kW and was the figure used to size the inverter pack.
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Pod 1 Power Requirements (64 Units)
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Appliance |
Wattage |
Hrs/day |
Units |
kWh/day |
kWh/mo |
| |
|||||
|
Light |
100 |
4 |
64 |
25.6 |
768 |
|
Laptop |
80 |
5 |
32 |
12.8 |
384 |
|
Hair Dryer |
1400 |
0.5 |
11 |
7.7 |
231 |
|
Microwave |
1200 |
0.5 |
11 |
6.6 |
198 |
|
Cellphone |
4 |
3 |
64 |
0.768 |
23.04 |
|
Total |
53.468 |
1604.04 |
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Aquaponics Power Requirements |
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| |
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Pumps |
500 |
24 |
3 |
36 |
1080 |
|
Fans |
50 |
24 |
6 |
7.2 |
216 |
|
Air Pump |
100 |
24 |
2 |
4.8 |
144 |
|
Light |
100 |
2 |
4 |
0.8 |
24 |
|
Total |
48.8 |
1464 |
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| SEGO Center City Hub Power Requirements | |||||
| (8 Suites/170 capacity dining room/3 Conference Areas/Laundry/Kitchen/Library) | |||||
| |
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|
Appliance |
Wattage |
Hrs/day |
Units |
kWh/day |
kWh/mo |
|
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|
Satellite Dish |
50 |
24 |
2 |
2.4 |
72 |
|
Computer |
300 |
2 |
15 |
9 |
270 |
|
Multi-media Other |
250 |
2 |
3 |
1.5 |
45 |
|
DVD Player |
50 |
2 |
3 |
0.3 |
9 |
|
Stereo/Music |
1000 |
2 |
3 |
6 |
180 |
|
Lighting |
100 |
4 |
50 |
20 |
600 |
|
Hot Tub |
20000 |
4 |
1 |
80 |
2400 |
|
Maytag Washer (Maxima 4.3 cuft) |
200 |
2.5 |
5 |
2.5 |
75 |
|
Maytag Dryer (Maxima 7.4 cuft) |
1000 |
2.5 |
5 |
12.5 |
375 |
|
Refrigerator (40 cuft) |
1000 |
6 |
2 |
12 |
360 |
|
Vacuum Cleaner |
1000 |
0.5 |
2 |
1 |
30 |
|
Walk-in Freezer (8′ x 6′ x 8′) |
0 |
2280 |
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Walk-in Cooler (10′ x 20′ x 8′) |
0 |
1600 |
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Dishwasher |
2000 |
4 |
1 |
8 |
240 |
|
Stand Mixer (30 qt.) |
2000 |
1 |
1 |
2 |
60 |
|
Griddle (3′ x 2′) |
1500 |
2 |
1 |
3 |
90 |
|
Oven |
10000 |
2 |
1 |
20 |
600 |
|
Total |
180.2 |
9286 |
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Grand Total |
282.468 |
12354 |
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SOLAR SIZING
Okay, so how do we go from kWh per day to PV arrays on the ground, and battery sizing, and inverter sizing, etc.? Here’s how Doug described it for us:
Looking at available sunlight for the property: The National Renewable Energy Labs (NREL) went out and measured sunlight availability for several hundred sites across the U.S., and they did it for 30 years. 1960 thru 1990. So we’ve got a nice average. This is the “NREL Redbook”, and is the standard source for estimating sunlight availability at any point in the U.S., for any time of year. For our location we have a yearly average of 5.9 hrs of peak sun per day. Peak sun? What’s that? That’s the scientific definition of full sunlight on the Earth’s surface. A “full sun” is defined as 1,000 watts per square meter. Now it’s immediately apparent that’s an impossibly round figure. And you’re right. Reality on the ground varies widely depending on humidity, altitude, sun angle, and a host of other variables called “the weather.” What NREL has done for us is to take all the hours of sunlight on a particular site and condense it down, as if all the hours were at perfect solar noon – 5.9 peak hours in this case. Which is pretty handy, because PV modules are rated to produce a certain amount of power at “full sun.” If we know a site averages a certain number of peak hours of sunlight, we can closely estimate how much power a given PV array will deliver. Now, a warning here, we’re talking about the weather. And it varies from year to year. In fact the NREL data clearly demonstrates that it varies by plus or minus 9% yearly. So it’s not worth getting too gnat’s ass accurate with our system sizing, as there’s bound to be yearly variations.
5.9 hours is the yearly average sun for our location. In December, at the lowest, it drops to 4.4 hours, which is still pretty good as solar sites go. For a December site, it’s excellent, and we’re going to use the 4.4 hour figure for PV system sizing. Now we know how many kWh per day your complex needs, we know what the average sun is going to be in December, what’s left is system efficiency. How much is lost to wiring, dusty modules, batteries, inverters, etc? Real world measured efficiency for battery-based systems ranges from 50% to 70%. Since much of the energy in this system will be used during daylight hours and will not need to be stored in batteries, I’m giving this system a fairly high 65% efficiency rating. This is completely seat of the pants estimation based on experience with large battery- based systems.
So we’ve got a 282.5 kWh nut to crack with 4.4 hours of peak sun and a 65% efficient collection and delivery system.
282.5 kWh / 4.4hrs / 65% = 98.77 kW of PV required. How many of what PV module is left until later, probably until right before purchase as prices and module brands have been shifting rapidly.
BATTERY SIZING
Batteries are the largest expense for the system. Lead prices just keep rising as the world becomes more industrialized. Lead-acid batteries still represent the best buy for remote systems. (And before you ask, lithium-ion batteries are still at least 4-5 times more expensive, and haven’t proved they’ll last longer than lead-acid. Who hasn’t had problems with phone or laptop batteries?)
When sizing off-grid battery packs we usually aim for about 2 to 3 days worth of storage capacity. Less capacity means the batteries get cycled deeply on a day to day basis, which isn’t good for life expectancy. More capacity raises the cost to where it’s cheaper to start the backup generator to meet the occasional shortfall.
Batteries are sized by amp-hours rather than watt-hours, so we have to divide our watt-hour figure by the battery voltage – 48-volt in this case. (If you remember your high school physics, watts divided by volts equals amps. Or volts times amps equals watts.) We also have to factor in how deeply we’re willing to cycle our batteries. The true deep-cycle batteries we’ll be using will tolerate cycles down to 80% depth of discharge (DOD), but again, deep cycles aren’t good for life expectancy, so we’re going to draw the line at 70% DOD. Considering the high quality of the Unigy II batteries we’ll be using, along with reasonable cycle depth, this battery pack should enjoy a 15 to 20 year life expectancy. By which point lithium-ion batteries may be a better choice. That’s a bridge to cross when we get there.
282,500 watt-hours x 2.5 days / 48 volt / 70% = 21,019 amp-hours @ 48v. This is one honkin’ BIG battery! To help make it more manageable, we’re going to use an SMA Sunny Island Multi-Cluster inverter package which divides the inverters up into four separate nodes, with each node having its own battery pack. And that brings us to…
INVERTER SIZING
Doug chose the Sunny Island Multi-Cluster inverter package for several reasons. It’s highly reliable and adaptable German engineering at its best. It consists of 12 individual Sunny Island 6kW inverters wired as four groups of 3 inverters each. So 12 x 6kW = 72kW, very close to the max AC surge requirement we estimated earlier. (Each 6kW Sunny Island can deliver 8.4kW for 1 minute, or 11.0kW for 3 seconds for true surges.) Each node of 3 inverters will cover the A, B, and C phases of your 208vac 3-phase system. As power demand increases, the Multi-Cluster will activate more nodes as needed. So we won’t have a lot of inverter capacity turned on, using power, and just waiting for something to happen. Capacity will only get turned on as needed. Each node has its own battery pack, which will make the individual packs more manageable. And if any one inverter or battery pack needs service, that node can be shut down, while the rest of the system will still operate normally. Also, the Sunny Island system uses conventional high-voltage grid-tie inverters to process the incoming PV power. So transmission from PV arrays hundreds of feet away are much less of a problem.
MAINTENANCE AND CONTROL
While this system is designed to be largely automatic and self-sustaining, there will be one or more designated maintenance and service personnel for the community. This person will be in charge of system operations, and trained to be familiar and very comfortable with the Sunny Island system. In addition, a great deal of system automation is possible with the Sunny Islands. As battery state of charge drops to critical levels, the Island can initiate start-up of backup generators, and/or shut down selected loads (the hot tub for instance). Routine maintenance includes cleaning PV arrays, snugging up battery cables, and monitoring the Multi-Cluster for any warnings or problems. For this reason, someone dependable and knowledgeable will be “in charge” of the system at all times.
ONE COMMUNITY ENERGY USAGE EXPLORATION
Sustainable energy, and renewable energy abundance, is all about careful planning and system redundancy. To prepare to supply electrical and heat “off-grid” energy for One Community starting on day one, an assessment of energy needs and an evaluation of available technologies to supply these needs was conducted by Lorenzo as well. We include this here as part of our open source sharing process of our exploration of adding to the foundation above to far exceed our needs estimates and provide a massive surplus of energy for ongoing One Community expansion. Semi-subterranean construction, use of time-tested passive heating and cooling, new innovations in heat from composting, use of rocket mass stoves, etc. will all contribute greatly to reducing our energy requirements but have not been incorporated into these calculations or this plan because of a lack of reliable data and a desire to err on the conservative side.
INITIAL ENERGY USAGE ANALYSIS
The typical family home in the United States uses from 2 to 4 kilowatt-hours (kWh) of energy per day. To sustain our initial community of 30-40 people, energy needs can be greatly reduced by conservation and timing peak-energy use during peak-energy supply availability. This initial estimate for One Community’s energy usage, however, will be based on general needs and is somewhat inflated. All costs and descriptions of generator energy systems are current as of April 2011.
Besides heating and water pump, the largest electrical energy uses in the typical home are in refrigeration and clothes washing/drying. Other electrical appliances are also listed in the table below for total electrical energy use per day for One Community.
One Community electrical usage before starting to build infrastructure will be 12.77 kWh. Adding a buffer for surge requirements for the startup of some appliances of 20-25% will yield a total figure of around 16 kWh.
ENERGY USAGE INITIAL SUPPLY
We have access to a propane and diesel generator capable of running our initial heating, refrigeration, and appliances. At startup, this system can be used and slowly phased out as more efficient and self-sustaining energy supplies are brought on line. Present off-grid systems include fuel-powered internal combustion generators, solar power, and wind power.
TRADITIONAL OFF-GRID SYSTEMS
Fuel-powered combustion generators are the stalwarts of off-grid electrical energy generation. These generators are powered by gasoline, diesel, propane/natural gas, or biodiesel. Considering their low cost and high reliability as a backup system, One Community will use the available propane powered system with the following replacement/upgrade costs in mind:
The prices vary widely on these generators and all above prices are for new units at retail. From a cursory look at generators on eBay, some units can be had at 50% off retail. Also, it should be noted that propane/natural gas generators can be converted to run on gasoline, and diesel generators can be converted to run on biodiesel at a minimum cost so One Community is considering the possibility of achieving its energy self-sustainability by making its own biodiesel.
CONSUMER SOLAR OFF-GRID SYSTEMS
All properties we would consider will have enough available sun for generating solar power with a minimum of eighty percent of the year as sunny. With this much sun, solar can be used to generate electricity with photovoltaic (PV) panels or generate hot water and heat with solar thermal panels and/or solar salt ponds.
Typical off-grid PV systems use a battery bank for continuous power (day and night), an inverter to convert the DC power into more common AC power, a charge controller for properly charging the battery bank, and a variety of wire, connectors, and other electrical components.
Below is a table listing some different sizes of Solar PV systems. Solar Panels are listed with number of panels, brand, model, and price. Battery bank is listed by brand, capacity, model number, and price. The inverter column lists brand, model, and price. The balance of system includes wiring, controls, disconnects, and other electrical components.
The main drawback to solar is the high initial investment. The initial investment can be reduced through leasing solar PV equipment and/or reducing power requirements by planning intelligently. Intelligent planning includes the use of DC power directly (DC appliances use substantially less power than AC appliances) and proper scheduling of peak power needs during the day. Investing in a battery-bank for continuous energy needs can provide continuous power, but batteries can be an expensive part of the solar system. However, proper planning and conservation can also reduce this cost.
SOLAR SALT PONDS
Another lesser-known solar technology is the solar salt pond. The solar salt pond uses a salinity gradient to trap solar radiation in a large pond. The water heats up to 200 degrees Fahrenheit and remains on the bottom of the pond due to the salinity of the water. This hot water can be used to heat liquids through a series of pipes on the bottom of the pond. The liquid in the pipes can in turn heat directly or produce electricity through an Organic Rankine Cycle Engine.
Several solar salt ponds have been demonstrated in Israel, Texas, and Australia. A half-acre solar salt pond with a depth of eight feet could provide 20 kWh of electricity day, night, summer, and winter.
The costs in constructing such a solar salt pond are listed below.
The advantages of using a solar salt pond for generating electricity include: no fuel costs, low maintenance, and 365 day/24-hour power generation. Disadvantages include: danger of spillage of saline water to environment, high initial investment, and large land usage. Also it should be noted that the Organic Rankine Cycle Engine generates electricity with a low temperature differential of 65 degrees Celsius and could be used to generate power from any heating source such as Concentrated Solar Thermal Arrays.
SOLAR HOT WATER
The typical household uses 20 gallons of hot water per person per day. For One Community’s initial 30-person household, 600 gallons of hot water would be required per day. This is a liberal estimate as conservation can reduce this number substantially.
As with solar PV systems, solar hot water systems are modular. As requirements change more or less capacity can be accommodated. Solar hot water can also be a very efficient way to heat during cold months but added capacity would then be needed to provide radiant floor heating using solar hot water.
Below is the breakdown for a few typical solar hot water systems.
WIND POWER
Wind power is provided by turbines, which convert mechanical energy into electrical energy. Wind power is a good complement to solar since it can provide energy 24 hours a day. Typically on an off-grid system wind power is used to charge the battery bank of the solar system at night. Below is a table listing some typical wind turbine capacities and costs:
CONCLUSION
One Community’s initial energy needs will be met by the available propane and diesel system. Very conservative accounting for the first year of building is accomplished by assuming fuel for the existing propane and diesel systems ($2,000). We will then begin building the above 283 kWh solar system ($490,000) and one new 720 gallon per day solar hot water system ($4,000). Our goal is to reduce these costs as much as possible through mutually beneficial strategic alliances and wholesale accounts.
