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Highest Good Energy: Conservation & Infrastructure

Energy infrastructure and conservation methods are foundational to the creation of self-sufficient and self-propagating teacher/demonstration communities, villages, and cities to be built around the world. This page is an open source and free-shared guide to the setup and expansion of off-grid energy infrastructure during the construction of teacher/demonstration hub food infrastructurevillage models, the Duplicable City Centerand beyond. Once on the property, we will further evolve the Highest Good energy® foundations and open source resources with additional implementation and research results of an even broader diversity of energy saving strategies and alternative energy infrastructure methodologies.

This page contains the following sections related to Highest Good Energy:

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WHAT IS HIGHEST GOOD ENERGY

One Community defines Highest Good energy as renewable and conscientious of the air, water, and land that we all share. It is also an active approach to energy saving strategies that we are implementing including semi-subterranean buildingshared social spaces, passive heating, cooling, and lighting, maximally efficient hot water heatingwater saving shower headsenergy saving lighting plans, and more. One Community’s Highest Good energy rollout is detailed below assuming zero initial energy infrastructure and starting with traditional generators, then building a comprehensive solar array, and expanding with the exploration and implementation of wind and newer technologies as they become available and can be determined to be superior to other alternatives.

 

WHY HIGHEST GOOD ENERGY

Highest Good energy, green energy, off the grid living, eco-living, going green, sustainable energyThe current global approach to energy is not sustainable. One Community sees open source sharing the complete off-grid setup and expansion of energy infrastructure for beginning teacher/demonstration hubs through well-established hubs of 400+ people as a needed and desired stepping stone to global energy sustainability. Our goal is to promote conservation, all sustainable energy providers and technologies, and the viability of complete energy sustainability. We see making small-to-large group energy self-sufficiency easier, more affordable, and more attractive as part of our comprehensive approach to evolving sustainability that will positively and permanently transform the world for everyone

 

WAYS TO CONTRIBUTE TO EVOLVING THIS SUSTAINABILITY COMPONENT WITH US

SUGGESTIONS     ●     CONSULTING     ●     MEMBERSHIP     ●     OTHER OPTIONS

CONSULTANTS ON OUR SUSTAINABLE ENERGY INFRASTRUCTURE

Doug Pratt: Solar Systems Design Engineer
Lorenzo Zjalarre: Physicist and Energy Efficiency Expert
Ramya VudiElectrical Engineer
Robert Seton: Solar Design Engineer and Owner of Solar Hybrid Design
Ron Payne: HVAC/Thermal Designer and Mechanical Engineer

HIGHEST GOOD ENERGY OPEN SOURCE PORTAL

project management software, open source software, teacher/demonstration village, objective fulfilled living, data gathering for The Highest Good, transforming the planet, global collaboration, working together, tangible time, One Community, ACE Application Open Source Hub, Open Source ACE, ACE Application

We are beginning with open source and free-sharing comprehensive strategies for energy setup and conservation through semi-subterranean buildingshared social spaces, passive heating, cooling, and lighting, maximally efficient hot water heatingwater saving shower headsenergy saving lighting plans, and the detailed energy infrastructure rollout and establishment plan outlined on this page. As we complete them, the open source resources list below will continue to expand with tools, tutorials, and DIY resources for duplication of all aspects of One Community’s energy infrastructure:

the One Community blog, One Community updates, transforming the global environment, transformational change, evolving living, One Community, One Community Global, creating a new world, the solution to everything, the solution to everything, the solution to anything, creating world change, open source future, for The Highest Good of All, a world that works for everyone, world change, transforming the planet, difference makers, sustainability non-profit, solution based thinking, being the change we want to see in the world, making a difference, sustainable planet, global cooperative, 501c3 sustainability, creating our future, architects of the future, engineers of the future, sustainable civilization, a new civilization, a new way to live, ecological world, people working together, Highest Good food, Highest Good energy, Highest Good housing, Highest Good education, Highest Good society What we’re working on now
Highest Good energy, green energy, off the grid living, eco-living, going green, sustainable energy Energy self-sufficiency phase-in for 20-400+ people
Solar array cost analysis and implementation details Solar array cost analysis and implementation details
duplicable city center, solution based thinking, One Community, SEGO Center, city hub, recreation center, eco center, sustainable living, ecological living, green living, eco-recreation, group laundry center, for The Highest Good of All Resource saving and efficient Duplicable City Center
Hydronic Systems Setup Hydronic systems setup and development for 20-100+ people
Heating and Cooling Icon Dome-home heating and cooling research, plans, and adaptations
Heating hot water, hot water heating Shower dome and toilet dome energy efficient water heating specifics
Highest Good Lifestyle Considerations Page: Materials | Cleaning Supplies | Lifestyle Practices | Toiletries | Technology | Hardware Highest Good lifestyle considerations and conservation strategies
water saving shower heads, water saver showerheads, water conservation, water use reduction, the best shower heads, showers that use less water, using very little water, reducing water use, water conservation, making water last, Highest Good water, One Community, showerhead review, shower head reviews, reviewing shower heads Water-saving shower head research and comparison strategy
Energy Self-sufficiency Solution Hub: Click here for the FAQ, tips, and tricks energy self-sufficiency solution hub How to make your build easier than ours and how to solve any problems we encountered in our build
Energy Self-sufficiency Maintenance, Care, and Upkeep: Click here to learn how to maintain all components of the One Community energy infrastructure Complete and on-going maintenance and upkeep details per our experience with all energy infrastructure components
Energy Self-sufficiency Collaborative Hub: Click here for the experience of others using our energy infrastructure related blueprints and designs Archive and database of others building similar structures including their experiences, adaptations, etc.

 

ENERGY INFRASTRUCTURE IMPLEMENTATION DETAILS

Before One Community (or any off-grid teacher/demonstration community, village, or city) can begin being constructed in earnest, an initial team will need to move to the property to survey the land and begin food infrastructure preparation, finalize development plans, and create the “pre-infrastructure” that needs to exist to support the construction of the official One Community infrastructure. This group will need access to electrical power before much else can be done. From that point forward, more extensive and permanent infrastructure will be built.

What follows is the specific plan for this energy rollout starting with the initial survey team of 0-20 people through our first 400. As part of our open source goals, this rollout is designed and described in detail to help those interested in duplication. Additional details will be added as we

Note: We are seeking further professional input to double check our work on sections in blue – join our team if you’d like to help. Prices are accurate as of 9/2014.

 

INITIAL SURVEY TEAM: ENERGY FOR 10-20 PEOPLE

Highest Good society, fulfilled living, enriched life, enriching life, living to live, how to live an enriched life, keeping it all running, sustainable living, social architecture, fulfilled living, thriving, thrivability, emotional sustainability, the good life, a new way to liveThe primary focus of the solution for the initial people to move onto the property must be providing electricity as quickly as possible. There is also a need for flexibility of the generated power in order to provide the group with access wherever we need it. This will be accomplished initially by diesel generators with a plan to purchase our battery banks and begin construction of the solar array the second month.

Equipment Needed for this Phase Cost Details
100 kW generator + add-on options $22,124 100 kW generator (2400 kWh/day possible) – see efficiencies chart below
Towable Fuel Tank $12,900 990 gallon towable fuel tank
Fuel cost for 1 month $2,480 Running at 16.8% for 5 hours/day (see below for details and efficiency graph)
Total $37,504

Note: Eventually the generators will be mounted permanently on slabs. Ideally we will also be able to phase them out completely at some point. This, however, will be the focus of future engineering endeavors and is therefore not discussed at this time. 

IMPLEMENTATION DETAILS FOR INITIAL SURVEY TEAM

In the beginning, the power needs will vary too much from day to day to start building longterm energy infrastructure. However, since the generators will be on trailers, we will be sure to have access to the required electricity when and where it is needed:

Landing Party Power Setup Overview

Landing Party Power Setup Overview

TASKS AFTER PURCHASING THE PROPERTY, BUT PRIOR TO “DAY 1”
  • Generator

    Mobile Diesel Generator

    Select # of gen-sets and their capacity: Current estimate of total capacity needed to cover the instantaneous power draw for the Earthbag Village and Duplicable City Center is ≈400 kW. To provide the flexibility to supply power where it is needed, the total capacity can be provided by multiple units (one 100 kW generator + two 175 kW generators = 450 kW total). At about a ton each, these would probably be best used on trailers for mobility. Later installations of generators would be permanently mounted on slabs.

The reasoning behind having a 100 kW gen-set first is that it will provide intermittent and mobile power for use on miscellaneous work sites throughout the property. The two 175 kW units would then be slab-mounted near the Duplicable City Center and the Earthbag Village (Pod 1), mostly to provide backup power for the Duplicable City Center which will service the most people and consume the majority of the power we generate.

  • Identify power needs for the “Landing party”: What absolutely NEEDS power and when is that power needed? (system sizing is dependent upon maximum simultaneous necessary usage). Possible items to consider are:
    • Tool chargers
    • Large equipment (cement mixers)
    • Lights and heat for camp
  • Size and obtain a fuel source: The fuel source should be sized to provide enough for the running of the generator at the team’s power needs for at least the amount of time the team is planning on this phase multiplied by a safety factor of 1.2.
    • For the Landing Party of 20 people we assume that we will be using roughly 4.2 kWh/day per person (from Pod 1 per capita energy consumption). Over the course of the day we can assume that we run the generator for 5 hours continuously per day meaning that during that 5 hours the generator is running at 16.8 kW or 16.8%. Using the graph below we find that the 100 kW generator will consume 3.34 gallons per hour at that load. Multiplying the number of hours by the fuel consumption rate gives us 16.7 gallons/day times our safety factor of 1.2 gives us a final value of 20 gallons per day for the average day.
    • Fuel storage on site would then be divided by 20 gallons per day to give us the number of days the fuel source can sustain the party. The 100 kW generator with the 250 gallon base tank would last the party roughly 12.5 days without filling. Fuel for an entire month would be 620 gallons total. At today’s prices that would come to roughly $2,480 per month for normal or $2,000 for farm diesel.

For easy fuel storage, a trailer would provide mobility for frequent refueling at a biodiesel fueling station or delivery service. For more permanent storage a bladder might be the best and most low-cost solution.

TASKS ON THE PROPERTY
  • Purchase one gen-set and tow it to the property with pickup truck or similar.
  • Transport fuel source to the property (see sizing information above).
Generator Power Consumption Projections

100 kW Generator Power Efficiency and Consumption Projections

Note: Fuel consumption per generated kW varies with electrical load when using a generator. The chart above shows average fuel consumption in relation to % output (load). Since this chart is for a 100 kW unit, the % load is equal to the kilowatt output (50% = 50 kW). We will be able to use this data as a guide to size the fuel source.

 

THE FIRST WAVE: POWER FOR 20-50 PEOPLE

Highest Good society, fulfilled living, enriched life, enriching life, living to live, how to live an enriched life, keeping it all running, sustainable living, social architecture, fulfilled living, thriving, thrivability, emotional sustainability, the good life, a new way to liveAfter the “landing party” has completed their site survey, identified the locations of all planned construction (specific for buildings to be built in first 5 years, plus long-term general plan), begun working on the infrastructure, and completed and gained approval for all the initial building plans, the rest of the Pioneer Team will move onto the property. At this point, enough planning will have been done to begin working on the long-term energy infrastructure while still allowing for flexible power generation for construction needs. This means beginning to build the entire solar array to eventually service the Duplicable City Center and Earthbag Village (Pod 1).

Equipment Needed for this Phase Cost Details
175 kW generator + add-on options $24,949 175 – 275 kW (4200 – 6600 kWh/day possible with one 100 kW generator and one 175 kW generator)
1000 gallon Fuel Bladder $2,406.69 1000 gallon fuel bladder
Fuel for 6 months 175 kW Gen or (100 kW generator) $20,248.70 ($14,624.06*) @28.6% for 4.2 hours per day (@50% for 4.2 hours / day*)
Energy Manager $14,294.00 SMA, Multicluster Box, 3-Ph for 12 x 120V, 60 Hz,
SI5048U, add MC-PB, UL listed off-grid only, MCB-12U
Solar Array X3 (with batteries)  $1,419,926.88  283 kWh (849 kWh/December day)
Total $1,419,926.88

* This is smaller for the same amount of energy production due to the increased efficiency of these generators when running at a higher percentage of its maximum.

20-50 PEOPLE POWER IMPLEMENTATION DETAILS

Power production at this phase of construction will include implementation of the complete energy infrastructure needed for powering the Duplicable City Center and Earthbag Village (Pod 1). The portable generator will be used for tool and other remote power needs, and main-site needs, until solar is installed and operating as the primary power supply for the Duplicable City Center and Earthbag Village (Pod 1) sites:

first wave power setup overview, off-grid power for 20-50 people

First Wave Power Setup Overview

The core of the Duplicable City Center and Earthbag Village (Pod 1) power systems will look like this:

Energy Setup Core

Off-grid Energy Foundations

First we will install the batter bank and power management systems so it can be charged using the generators. We will then begin our transition to solar power by connecting the solar array to the system as quickly as possible to decrease use of the generators.

Note: The battery bank does not need to be full size yet, but must have the capability of increasing to that size in the future.

Based on our energy needs we will also:

  • Purchase additional 175 kW diesel generators to connect into the power management system for distribution.
    • Add the two 175 kW generators to meet power requirements for the completed Duplicable City Center and Earthbag Village (Pod 1). Fuel acquisition will be calculated by using the same principles for sizing and providing fuel as described above. These 175 kW generators will be mounted or placed on permanent concrete slabs near the Energy Manager, Duplicable City Center, and Earthbag Village (Pod 1).
    • Generators will be added piecemeal with the first 175 kW generator coming in midway through (or when load demands it) and the second added upon the activation of the Duplicable City Center radiant floor heating.
  • Keep the 100 kW generator non-permanently connected to the system (on the trailer) so it may be moved to provide power to remote construction projects and emergency power where/as needed.

Here are the 175 kW generator power efficiency and production projections for comparison with the chart above. Comparing these projections will help us maximize efficiency and minimize fuel use for our generators.

175 kW Generator Power Efficiency and Consumption Projections

175 kW Generator Power Efficiency and Consumption Projections

 

THE SECOND WAVE: POWER FOR 50-100 PEOPLE

Highest Good society, fulfilled living, enriched life, enriching life, living to live, how to live an enriched life, keeping it all running, sustainable living, social architecture, fulfilled living, thriving, thrivability, emotional sustainability, the good life, a new way to liveBy now, construction of the initial components of One Community are in full swing and we’re ready to bring on additional team members to accelerate the pace of progress. Along with population increases we will see the demand for electrical power and hot water increase. For instance, the Duplicable City Center kitchen and large-scale laundry facility will both be fully operational during this time and draw considerable electric power. As the demand grows, we will increase taking advantage of the energy efficiencies that are associated with larger systems like these and implement additional energy reduction and conservation measures too.

Equipment Needed for this Phase Cost Details
175 kW generator + add-on options $24,949 175 – 350 kW (4200 – 8400 kWh/day possible with both 175 kW generators now up and running and the 100 kW generator as a more mobile backup)
1000 gallon Fuel Bladder $2,406.69 1000 gallon fuel bladder
Fuel for 6 months 175 kW Gen or (100 kW generator) $25,284.10*($29,248.13) @50% for 4.8 hours per day* (@50% for 8.4 hours / day)
Wind Turbine(s)? ?? We will have the necessary experience with our location to effectively evaluate this option by this point
Flow Battery | Forbes Article About This ?? This technology (or other large-scale options) should be ready for market by this time
Total 52,639.79 This number will meet our needs and the addition of wind turbines, flow batteries, or other options will only be considered if proven financially and sustainably superior to other options

* This is smaller for the same amount of energy production due to the increased efficiency of these generators when running at a higher percentage of its maximum.

50-100 PEOPLE POWER IMPLEMENTATION DETAILS

As development continues, the hydronic systems become operational and the total load on the Energy Manager will increase. As energy saving measures are added, the load will decrease. Overall, our total demand for power, both hydronic and electrical, will increase. This construction period will be very energy-intensive and will require large amounts of fuel. The Duplicable City Center radiant heating will be the largest consumer of power (both hydronic and electric). Therefore, it will be beneficial to have the core energy system (all solar arrays) and some of the energy-reducing measures in place before the hydronic system is enabled. Further evaluation on the property will dictate whether wind power solutions are viable.

The following are the action steps for this phase of energy infrastructure development:

  • Start expanding the solar capabilities of the property.
    • Every kWh created by solar arrays reduces the amount of fuel that needs to be purchased and transported to the property
    • Experiment to identify best practices for our solar/electrical conversion
    • If possible, we may want to research creating biodiesel on the property to reduce our reliance on external fuel sources
  • Find a permanent position for the last of the 3 generators. We’ll be foregoing mobility, but we’ll need all the generators connected during this time of significant energy usage
  • Make a decision about the wind turbines and large-scale and longer-term energy storage options

Related to the last bullet-point above, here are the viability projections for energy storage starting with small amounts of energy being stored for less than a day and progressing to megawatts being stored for a year or more. The red line is our power demand and what you see is that with storage capacity there is an amount of stored energy that can offset cost in the different mediums: batteries, compressed storage, etc. If we need to store power for 1 month, batteries are not a viable solution, but hydrogen storage would be once energy storage needs are sufficient to warrant the added expense of creating infrastructure like this.

Energy Details, One Community

Different Energy Storage Solutions

 

THE FIRST FIVE YEARS: POWER FOR 100-400 PEOPLE

Highest Good society, fulfilled living, enriched life, enriching life, living to live, how to live an enriched life, keeping it all running, sustainable living, social architecture, fulfilled living, thriving, thrivability, emotional sustainability, the good life, a new way to liveThroughout the first five years on the property, One Community will construct several key structures. These will include the Duplicable City Center, the Earthbag Village (Pod 1)Straw Bale Village (Pod 2)food greenhouses, and additional village models if possible. The expectation from residents working in these areas and visitors touring our community will be that the solutions we are testing and displaying are genuine and practical solutions. During this time the Phase I energy system (described above) will be completely developed and the new focus will be testing and monitoring this system, fine tuning and conservation strategies, and planning and implementation of next steps.

Equipment Needed for this Phase Cost Details
To be determined TBD We will choose this development phase of energy infrastructure based our open source duplicability goals and global transformation values and strategy. It will be paid for by our revenue streams.
100-400 PEOPLE POWER IMPLEMENTATION DETAILS

This phase of development will be about monitoring all electrical energy being consumed and making expansion decisions based on needs and what we learn. The monitoring will be accomplished through meters for all individual living spaces and ammeters on any main power lines that would output the amps being used at that instant. Since the voltage will be known, the power will then be a simple calculation done by either a designed system or one bought off the shelf. That power (in Watts or kW) will then be logged over time to get the amount of energy in kWh used during the course of the day.

The following picture illustrates this with each “A” representing a monitoring point that communicates with a power display feeding data to central data analysis point:

Power monitoring example

Monitoring Electrical Energy Used by 100-400 People

Electrical Power Monitoring will have displays at the source and connections to a Main Power Display that will monitor and control electrical energy management sub-system.

Similarly, hot water used in showers, domestic use, and hydronic systems can be monitored by knowing the flow rate, temperature, and amount of time used. With instantaneous water heaters at points of service, the electrical energy draw from those units could also be used with the addition of the known hot-tank water temp and the flow rate of the use.

hot water monitoring, energy use

Hot Water Monitoring and Data Analysis

In short, hot water monitoring needs two pieces of data for each point: temperature and flow. For showers and the boiler, temperature can be replaced by an electrical power reading which will already be monitored by the electrical energy monitoring software and relayed to the Main Power Display. For everything else, temperature and flow monitors will do the job.

Specifically monitoring all of these things will allow us to fine tune our consumption patterns and open source share our results. Tracking these metrics for guests will also be a major benefit to the mission of One Community by showing the constant flow of temporary residents/visitors an accurate report of their energy usage while staying. In so doing, we help to educate people and give them the opportunity to become more conscientious about their use.

This will also create ultra-accurate energy needs assessments to help us with our planning and construction of each additional open source village needed for expansion to host people beyond the initial 400.

 

THE LONG TERM: POWER FOR 400+ PEOPLE

Sustainable energy, and renewable energy abundance, is all about careful planning and system redundancy. We won’t be able to effectively plan our power needs beyond the Earthbag Village (Pod 1) and Duplicable City Center until both of these components of our infrastructure are complete and we’ve gained the experience of using the systems designed above. While it is predictable that we will actually increase our energy efficiency over time due to increased conservation methods and “fine tuning” of our usage patterns, it is also predictable that we will have energy needs we haven’t accounted for.

Learning from experience, learning more about our specific property and how effective options like wind power may be, possible implementation of new energy technologies, and a better understanding of our specific needs will all be crucial to planning our power infrastructure for the Straw Bale Village (Pod 2) and beyond. Here are a few options we’ve explored to demonstrate cost differences and energy production potential.

WIND POWER

Wind power is provided by turbines, which convert mechanical energy into electrical energy. Depending on how windy a property is, wind power can be a good complement to solar because 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:

SOLAR SALT POND

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 (93 degrees Celsius) 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 (2.4m) 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.

SOLAR HOT WATER

We’ve already designed an extensive hydronic system that includes solar hot water. Expanding this system in the most intelligent manner possible will be based on our experience with the first system, technology advances, and clarification of expansion needs. As with solar PV systems, solar hot water systems are modular and this will provide us increased opportunities for expansion as our requirements and initial hydronic systems function and effectiveness becomes clear. For comparison, here are a couple typical solar hot water systems and their capacities.

OTHER ENERGY OPTIONS

We are contacted almost monthly with a new energy option. Once we are on the property we will have all our team in place and people can bring these ideas to demonstrate them. If we can verify a working model from someone willing to open source and free-share it with the world, we see no place better than an organization like ours to do so. We’ll also be able to consider funding addition research of such systems at that time.

 

SOLAR ARRAY COST ANALYSIS

One Community’s off-grid energy infrastructure to supply the Duplicable City Centerthe earthbag village (Pod 1), and aquaponics sustainable food infrastructure was initially assessed to require 283 kWh of power and we sized our photovoltaic solar power system to meet these needs. As per the energy self-sufficiency phase-in for 20-400+ people section above, these original assessments have proven far insufficient for our needs. Until we have completed our new needs analysis, we include here the details for the original system purposed to produce 283 kWh/day under average December sun conditions at the One Community property.

We have chosen a photovoltaic system as our initial energy infrastructure because these systems are dependable and capable of being shipped and duplicated anywhere in the world. We will use generators (as described aboveas 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 the straw bale village (Pod 2) and beyond.

NOTE: THIS PAGE IS NOT CONSIDERED BY US TO BE A COMPLETE AND USABLE TUTORIAL UNTIL
WE FINISH THE COMPLETE DUPLICABLE CITY CENTER AND EARTHBAG VILLAGE (POD 1)
BUILD AND ADD ALL THE VIDEOS AND EXPERIENCE FROM 
AN ON-SITE ELECTRICIAN
AND THE ENTIRE BUILD TO THIS PAGE. IN THE MEANTIME,

WE WELCOME YOUR INPUT AND FEEDBACK

The following price quote is current as of January 2013.

Item Description Qty. Unit Price Ext. Amount
PV-based power system designed to deliver approximately 283 kWh/day under average December sun conditions at the One Community property
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

 

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:

      1. 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
      2. Open source sharing videos and tutorials for the building and setup process
      3. 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 THIS INITIAL 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 and our initial guess missed the mark when we A) realized rocket mass heaters would not be a viable option for the earthbag village and B) that heating the Duplicable City Center and operating the large-scale kitchen was going to be far more energy intensive than we originally expected.

So now we are redesigning the above system with precision and all the new details of our ongoing development progress. Also, it is important to state that humans are nothing if not variable and we anticipate that this system will almost certainly require some fine-tuning even though we are doing our best to account for even the most minute details. 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 homes, the Duplicable City Center, 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 the earthbag villageaquaponics, and the Duplicable City Center, on a yearly average, was initially 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 homes, 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.

An Updated Version of this Information is Coming

Pod 1 Power Requirements (72 units)
Screen Shot 2013-01-16 at 8.58.41 PM
Appliance Wattage Hrs/day Units kWh/day kWh/mo
 Screen Shot 2013-01-16 at 8.58.41 PM
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
 Screen Shot 2013-01-16 at 8.58.41 PM
Aquaponics Power Requirements
 Screen Shot 2013-01-16 at 8.58.41 PM
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
 Screen Shot 2013-01-16 at 8.58.41 PM
Duplicable Center City Hub Power Requirements
(12 Suites/170 capacity dining room/3 Conference Areas/Laundry/Kitchen/Library)
 Screen Shot 2013-01-16 at 8.58.41 PM
Appliance Wattage Hrs/day Units kWh/day kWh/mo
Screen Shot 2013-01-16 at 8.58.41 PM
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
Walk-in Cooler (10′ x 20′ x 8′) 0 1600
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
 Screen Shot 2013-01-16 at 8.58.41 PM
Grand Total 282.468 12354

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:

Highest Good society, fulfilled living, enriched life, enriching life, living to live, how to live an enriched life, keeping it all running, sustainable living, social architecture, fulfilled living, thriving, thrivability, emotional sustainability, the good life, a new way to liveLooking 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 hyper-sensitive to accuracy 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

Highest Good society, fulfilled living, enriched life, enriching life, living to live, how to live an enriched life, keeping it all running, sustainable living, social architecture, fulfilled living, thriving, thrivability, emotional sustainability, the good life, a new way to liveBatteries 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

Highest Good society, fulfilled living, enriched life, enriching life, living to live, how to live an enriched life, keeping it all running, sustainable living, social architecture, fulfilled living, thriving, thrivability, emotional sustainability, the good life, a new way to liveDoug 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.


RESOURCES

 

SUMMARY

Highest Good energy, green energy, off the grid living, eco-living, going green, sustainable energyCompletely off-grid energy production in remote locations requires planning and a detailed phase-in process if the goal is to build as effectively and efficiently as possible. One Community is open source sharing our design process and rational as a foundation of establishing self-sufficient and self-propagating teacher/demonstration communities, villages, and cities. We will evolve this page with more details as they develop. These details will eventually include complete installation tutorials, maintenance details, purchase order specifics, and more.

FREQUENTLY ANSWERED QUESTIONS

Q: How are the generators sized?

Generators are sized using the maximum continuous wattage (power) that they can reliably create. If, when every device is turned on and running at maximum, the power draw is 95 kW then we select a 100 kW generator. Most of the time the power draw on the generator will be much less than the maximum load.

Q: How is the system sized?

The energy system will always be designed for the worst-case, maximum load. This would include sizing wires, fuses, and busses to handle every possible device and appliance turned on at once. Even though this is a very unlikely scenario, it ensures that the system will always work within its safe limits.

Q: In what case would the generators activate?

In the beginning we will use the generators for many different activities, but as the project adds sustainable energy sources to the property the generators will be phased-out in favor of the more sustainable options. However, we will keep the generators on site, in running order and fueled in case of a fault in any part of the energy management system. Or to as make-up energy for the system.

Q: What happens in the case of a massive battery fault?

In this scenario the battery banks are damaged or in some way inhibited from providing the stored power back to the energy manager. As the energy manager senses the drop (or stop) of battery power it will send a “Start” command to the backup generators causing them to start, reach working RPM, and sync into the energy manager’s grid. During this time the total load of the project less the total amount being created by sustainable means at that instant would be placed on the generators. They would run until battery storage was back online or the sustainable systems were creating enough power to cover the current load.

Q: What happens when there is not enough power to charge the batteries? (Cloudy Week Scenario)

Sometimes there will be a deficit of energy created in the day (solar, wind…etc.) and the remaining energy needed will have to be “made up.” The energy manager will run one or more generators at the most fuel efficient load for as long as it takes to charge the system. Once charged, the energy manager will automatically shut down the generators. In times of low light due to atmospheric disturbances this could become a daily occurrence to meet the forecasted demands on the system.

An example would be the energy manager calculating the amount of energy in storage and if the stored power does not meet the energy needs of the system for the next 24 hours the generators would run after the solar cycle (evening) to “top off” the batteries for the following day.

Q: What happens in the case of an energy manager malfunction?

In the case that the energy manager fails to operate or detects a fault, the system would go under total generator control. Because improper battery management can cause catastrophic damage, it is safer to allow the generators to take on the entire load of the system and remain in that state until the energy manager fault is discovered and fixed.

Q: How does the system change in an emergency scenario?

As a fault is detected in the system the energy manager, programed in advance, will compensate by utilizing the different power storage and production equipment options that are connected to the system.

Normal management would be the phasing in and out of sustainable power sources as they come online. However, in the event that a subsystem fails in such a way that could be damaging the entire system, like a short circuit or an unexpected voltage spike, the manager will remove the offending device from the system and rely on other sources. Mechanical systems (fuses, breakers) will also be in place in the case of a very sudden change in voltages that could be too quick for the manager to compensate, such as a lightning strike or short.

Q: What are the fail-safe measures?

Whenever possible all parts of the system will be designed to fail in a way that provides the safest possible scenario for the rest of the system. Whenever possible the system will also continue to provide power. This said, there could still be times where a catastrophic failure fail-safe would be to cut power completely. The details of this system of fail-safes would depend on the environment in which the system is placed and it’s particular construction and components, so at this time there are no definitive plans.

Q: What systems would be active in a power emergency?

In a power emergency only essential systems should be left on. The following factors would determine which systems are essential:

  1. The severity of the power emergency: The more severe the emergency, the more systems that would need to be turned off.
  2. The season: Heaters, for example, would be non-priority in the middle of summer and crucial in the winter.
  3. Consideration of how often a specific unit is drawing power: If the system is off most of the time it might not hurt to leave that unit in an off state.
  4. The power draw: If the the hot tub circuit draws 200 times the power that the lights in the Duplicable City Center does, it would be useful to turn that device off, before the lights go out.
  5. Importance of systems: As in the hot tub example in #4, systems that closely relate to human basic needs (food, shelter, water, etc.) should be prioritized. To make power conservation easy in an emergency, priority circuits should be marked both physically and in the energy controller.

To help put the energy needs of different systems in different situations into perspective, here is a chart showing how much specific components of One Community will contribute to peak wattage needs:

Emergency Power Peak Wattage Pairto

Emergency Power PEAK Wattage Needs Assessment

Now compare this to this chart that shows how much specific components of One Community will contribute to total energy needs:

Emergency Power Total Wattage Needs Assessment

Emergency Power TOTAL Wattage Needs Assessment

The point of these two charts is to show that components like the heat pump, dryer, and water heaters draw the most power from the perspective of total daily needs because they will be running consistently. Individual heaters, the boiler/water heaters, dryer, and parabolic heaters are the top contributors to peak wattage (energy spikes) because they draw a lot of power at one time. The general trend is still that those items high on one chart are also high on the other chart, but the details will vary and this can be extremely helpful to understand and consider in emergency power situations. Also, to conserve power, the hot tub (a huge energy consumer) has been designated as an item to be used only when surplus energy is available (like in the summer months).

Q: How much bio-diesel will you need?

The fuel source should be sized to provide enough for the running of the generator to meet team power needs for at least the amount of time the team is planning on this phase multiplied by a safety factor of 1.2. For the Landing Party of 20 people we assume that we will be using roughly 4.2 kWh/day per person (from Pod 1 per capita energy consumption). Over the course of the day we can assume that we run the generator for 5 hours continuously per day meaning that during that 5 hours the generator is running at 16.8 kW or 16.8%. Using the graph in the related section above, we find that the 100 kW generator will consume 3.34 gallons per hour at that load. Multiplying the number of hours by the fuel consumption rate gives us 16.7 gallons/day times our safety factor of 1.2 gives us a final value of 20 gallons per day for the average day.

Fuel storage on site would then be divided by 20 gallons per day to give us the number of days the fuel source can sustain the party. The 100 kW generator with the 250 gallon base tank would last the party roughly 12.5 days without filling. Fuel for an entire month would be 620 gallons total. At today’s prices that would come to roughly $2,480 per month for normal or $2,000 for farm diesel.

Q: What are the benefits of bladder storage for fuel?

Storing fuel in a large bladder is by far the most economical way to store the biodiesel used by the generators. However, bladders are flimsy and easily punctured. They cannot be buried either, so they would have to sit on the ground somewhere protected from heat-sources, and sharp objects.

Q: What are the benefits of tank storage for fuel?

While Tanks are more expensive than bladders, they can be buried to keep them away from heat sources and punctures. Larger tanks would take a large piece of land-moving equipment to place underground.

Q: How long will the batteries take to drain?

Very simply, batteries are rated with their voltage (average) and Amp-Hours. A 50 A-hr 12-volt car battery will provide 1 amp at 12 volts for 50 hours, or 50 amps for 1 hour, or 25 amps for 2 hours, etc. This is the principle used to size the batteries needed on the property. Knowing that we need to provide a certain amount of power (lets say 5 kW) over a certain amount of time (2.5 days = 60 hours) we can start to calculate the batteries needed.

Typical high-voltage batteries can be around 48 volts. Knowing that Volts X Amps = Watts, we can determine the number of amp hours needed:

  • 48 volts X (?) amps = 5000 W (5 kW)
  • (?) amps = 5000 W / 48 volts = 105 amps (rounded)

Since we need that over the course of 60 hours:

  • 105 amps * 60 hours = 6300 amp-hours

If the largest size of battery we can find is 1000 A-H, then we would have to buy 7 of them to cover this draw for 2.5 days.

  • 6300 A-H / 1000 A-H = 6.3 → 7

As with all engineering calculations, the largest (predicted) average power drain will be taken into account to build in a buffer to our system.

Q: Why not use the grid?

Most solar power systems in the United States (and other first-world countries) use the grid as a backup source and storage system. When the system is producing more power than is needed the system provides power to the public grid for others to use. The electric company measures this and creates a credit (in $$) to the person’s account with them. In times of decreased solar power production the credits are used to pay for the remaining energy needed that is not provided by the solar array. If the system is sized correctly the balance over the course of the year will be $0.

Why don’t we do this? There are two primary reasons:

  1. Duplication: Not every teacher/demonstration hub will be near a stable and well-maintained power grid with an agency that is willing to buy power back. It is up to us to take on the hard task to provide solutions to those that need them most.
  2. Sustainability: Although solar power is sustainable, in the grid-tied system above a part of the year the power comes from using grid power which, depending on where you live, may not be from renewable sources. Our goal is to promote and support the most sustainable options possible.

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