This page is part of the Highest Good energy component of One Community and an open source guide to setting up a solar micro grid (with wind power also) for the Duplicable City Center® and Earthbag Village. It is purposed to help people understand the how’s and why’s of design and setup for replication and better understanding and implementation.
We discuss this with the following sections:
NOTE: THIS PAGE IS NOT CONSIDERED BY US TO BE A COMPLETE AND USABLE TUTORIAL UNTIL
WE FINISH OUR OWN DEMO CONSTRUCTION AND ADD ALL THE VIDEOS AND EXPERIENCE FROM
THAT BUILD TO THIS PAGE – IN THE MEANTIME, WE WELCOME YOUR INPUT AND FEEDBACK
A microgrid is a localized generating station to meet the power needs of a local community. In our case, the localized generating station generates power from solar and wind energy, called distributed energy resources (DERs). Typically, a microgrid is designed to meet the demands of the locality in “islanded mode” where the microgrid is running self sustained and off-grid. To ensure power at all times, the utility grid is still connected to the microgrid and drawn upon as needed.
Because solar and wind energy are intermittent in nature, the following equipment is used in the microgrid to efficiently deliver power:
Our goal is to make solar an easier do-it-yourself project. Solar technology is not rocket science, but there are numerous technical terms and standards people should be aware of before implementing any changes to their energy infrastructure. To help with this while also teaching all that is needed for replication, we are open sourcing here everything for the Duplicable City Center and Earthbag Village Microgrid. As they occur, we will open source additional evolutions for the other 6 villages too.
The Duplicable City Center is designed with 12 visitor rooms and shared social spaces to accommodate approximately 200-300 people. The Earthbag Village consists of 72 individual residences to accommodate approximately 150 people. By open sourcing the process and details for the microgrid setup for these two constructions, and later the other 6 villages, food infrastructure, etc., our desire is to provide the knowledge necessary for:
Off-grid energy infrastructures, also referred to as “microgrids,” are a non-conventional form of power generation that are becoming more and more popular for off-grid design and/or anyone concerned about grid stability. They work independently or in conjunction with the grid in order to reduce stress on existing infrastructure while strengthening grid resilience. Some of the advantages of microgrids are:
The concept of microgrids could be an energy game changer because they decentralize the conventional power system model. Every power system involves generation, transmission, and distribution. But in the case of microgrids, power is generated as close as possible to the distribution end. Thus the term “distributed energy resources” (DERs).
DERs are typically renewable sources of energy, the most widely used being solar and wind. These sources are readily available and among the most efficient sources. When part of a microgrid, they also offer always-on power through multi-mode backup options like grid-connection and/or backup generators, avoiding the sometimes significant expense of power outages.
Here we discuss details of micro-grid design and implementation with the following sections:
The sun rises every day and even areas with large amounts of rain can provide solar energy. It is just a matter of how much and whether or not it is sufficient to justify the cost of solar over other energy options. Using free resources like Google’s Project Sunroof or NREL’s Solar Maps, you can check the viability of solar for your location. Our location shows solar is very viable and so is wind. If it is a good choice for your location you can also be happy about these additional solar benefits:
This image explains how this works:
Here is a video about how microgrids work and are helping in California:
In order to acquire maximum power output from the panels, they need to get as much sun as possible. This means they should be placed somewhere without shadows, on the south side of structures, and at an an angle based on your site’s latitude.
This picture shows a general example of the difference in the Sun’s path and angle during the summer versus the winter:
The sun specifics for each location is different and these sites can be used to determine the best angle(s) for your panels.
Here is a more detailed image showing our location’s sun angles with an additional time of the year for the open source Tropical Atrium:
Another consideration when setting up your microgrid is the distance from the grid to the point of use. The longer the distance (and hotter the temperature) the more potential for power loss. Longer distances (and increases in heat) are compensated by using larger (and more expensive) wire; but shorter distances are more efficient.
To further clarify and determine your own calculations, this website calculates voltage drop based on distance and temperature:
Power to be produced/generated is determined as a total of load demand (how much power is needed by equipment) and losses incurred (how much power is lost by equipment, wiring, etc.).
i.e. Generation = Load Demand + Losses
This is the conventional method of determining the power to be produced. With both a conventional grid and an off-grid (or grid-tied) microgrid, losses are categorized into fixed (guaranteed to happen) and variable (dependent upon system design). They occur due to heat dissipation.
Fixed losses would be:
Variable losses would be:
Note: As mentioned before, microgrids are installed on the distribution end – meaning installation and power collection happens where the power is needed. Thus, transmission losses are negligible.
In case of a solar microgrid, the concept to determine the power generated is the same as a conventional grid: load + losses. The method and technical terminology used will be different though with a microgrid. This is because we are working with solar panels, batteries and inverters rather than traditional-grid generators, transmission lines, etc.
With a microgrid based on renewable, intermittent solar power, the following terminology is helpful to understand (and different from) a traditional grid-tied system:
R = ρL / πr2
Low resistance in turn, reduces the system losses. System losses are directly proportional to the conductor resistance squared times Current (I) through the conductor as the constant factor:
System Losses = I x R2
The I-V graph below gives a detailed explanation of parameters to observe while determining the solar panel.
A typical off-grid PV solar system looks like the figure below:
Image Source: www.nachi.org
Here are descriptions of all the equipment seen in the figure above:
To help with further understanding, here’s a video about how solar panels work:
This idea of a solar microgrid can be expanded to a solar/wind hybrid design as well. We know that solar and wind are complementary sources of energy and an analysis of a wind microgrid has been performed as well.
To meet the needs of both the Duplicable City Center and Earthbag Village, an intertie between the two has been designed for redundancy and reliability reasons. Any variability in the demand of energy in one structure can therefore be met with the help of power generated from the other structure(s) and vice versa:
In case of expansion, an economical design should also take into consideration the following factors related to placement:
VIDEO COMING OF: SYSTEM EXPANSION PROCESS – THIS TUTORIAL WILL SHARE WHAT WE LEARNED ABOUT PLACEMENT AND INTERTIE SETUP FROM OUR OWN EXPANSION PROCESS
The sizing of each equipment component in the microgrid design is calculated from the base data for total consumption (click here for our spreadsheet). In our case, the system design is an intertie, so the initial system is based on the calculated consumption of the Duplicable City Center combined with that of the Earthbag Village. Additional expansion will also occur with the construction of Villages 2-7, but the initial solar setup will provide all the power needed for the Duplicable City Center, Ultimate Classroom, Earthbag Village, and Phase I food infrastructure.
With our own system as an example, we discuss here the details of sizing a solar system with the following sections:
The first step for calculating the solar-sizing specifics is to identify the total power consumption. Total power and energy consumption = Total watt-hours/day (Wh/d), so the total consumption is the sum of individual equipment consumption in the Duplicable City Center. You can see these calculations for the Duplicable City Center on this spreadsheet: Click for City Center Spreadsheet.
The next step is to determine the equipment sizing. For this, you will need the rating of the PV module. The PV rating can be found by taking into consideration two factors: losses and insolation. The standard number used for “losses” is about 30%, and this accounts for dust on the panels, indirect sunlight losses, etc. Taking this into account, a loss factor of 1.3 is included in the total power demand so total power produced = 1.3 * Total Wh/day.
“Insolation” is known as the the amount of solar radiation reaching a given area and is expressed in kilowatt hours per meter squared per day (kWh/m2/day) and varies site-by-site. To determine this value, NASA has a detailed database providing the monthly insolation for any site input based on its latitude and longitudinal coordinates. An average of all months is then taken.
Once you know total watt hours and (average) insolation values, use this formula to find the Total watt Peak Rating:
Finding the size of your complete solar array/modules is then accomplished using the Total Watt Peak Rating (provided above) divided by the Rated Output Watt-peak of the module. The Rated Output Watt-peak of a module is acquired once the model of PV panel is decided (see Factors Affecting Equipment Selection below) and then this formula is applied:
Note that the number of PV panels is always a whole number. Therefore, irrespective of the solution, round the value to the next highest integer.
As mentioned above, inverters are the equipment that help convert DC power produced at the panels to AC to meet the load demands of all the standard equipment in the building(s), which is all AC powered. This is important because DC power will not power this equipment.
With this in mind, input rating of the inverter is selected so it is greater than the total power consumed by all the connected appliances. This value is typically 25-30% more than the total power consumed by the appliances. This 25-30% addition assures needs are met even during the most extreme energy demands, assuming to never exceed 25-30% beyond your calculated maximum.
As mentioned earlier, batteries come into the picture incase of insufficient power or absence of solar. Battery-sizing is necessary for off-grid Solar PV infrastructure. Solar PV systems typically require deep cycle batteries. These batteries have an advantage of rapidly charging and discharging to a low energy level, making them highly efficient. Batteries are rated in Ampere-hours. To find the Ampere-hour rating for a given solar PV system calculate the per-day consumption of appliances in watt-hours. The standard loss in batteries is typically 20%. This accounts for the charging and discharging cycle losses. Taking this into account, a loss factor of 1.2 is included in the total power supplied = 1.2 * Total Wh/day.
Practically speaking, it is not advised to drain batteries completely. This helps increase their lifespan. Due to this, batteries can be discharged up to a certain depth. This is termed as Depth of Discharge (DOD). Typically, DOD is taken as 60% on an average. This means the battery can be discharge till 60% of its energy has been delivered.
Taking into account 60% of the delivered energy, a factor of 1.6 is included in the total power supplied by the battery = 1.6 x 1.2 x Total Wh/day. The nominal DC voltage of a battery is the same as that set for the inverter. Considering economic and technical factors we have set the nominal voltage at 24 V, as further explained in the controls section. For any off-grid Solar PV System it is not advisable to charge and discharge the batteries every day. The “days of autonomy” designs the battery rating based on number of days the batteries deliver power without a charge.
Now that we have all the parameters required to calculate the Ampere-hour rating of the battery, the following formula is applied:
Charge controllers increase efficiency and lifespan of the batteries and the technology implemented in these controllers continuously evolves. We considered two factors in their design rating:
Relative to the I-V characteristics, the charge controllers are set at a rating of 1.3 x The Short Circuit Current. This procedure is implemented in the excel sheet where there is a detailed analysis of the cost estimates.
Here are additional considerations to include when selecting equipment. We will add more if our experience purchasing and installing our system reveals anything beneficial.
Three variations of solar panels are generally utilized for residential and commercial purposes: monocrystalline, polycrystalline, and thin film. They vary in silicon content, efficiency, area required, and cost, with preference given to the latter two.
The calculations for inverter sizing helps decide the inverter to be chosen. Apart from that, cost and the project budget aids in choosing an inverter as well.
As previously mentioned, deep-cycle batteries are preferable for PV systems; other factors include price, capacity, and voltage.
Following the above mentioned procedures, these figures were obtained for the sizing of the PV system equipment for the Duplicable City Center. The process continues to evolve though and our most current calculations can be found on the GoogleSpreadsheet.
These calculations have not been completed yet. If you have the necessary knowledge and experience and would like to help complete them, click here for the application to join our team.
These calculations have not been completed yet. If you have the necessary knowledge and experience and would like to help complete them, click here for the application to join our team.
Penetration of the microgrid is a combination of:
Both of these are addressed in detail with the step-by-step energy self-sufficiency phase-in for 20-400+ people plan shared on the Highest Good Energy open source hub: https://www.onecommunityglobal.org/highest-good-energy/#phase-in
While this system is designed as 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 troubleshoot all aspects of the system. Additionally, a great deal of system automation is possible with the Sunny Islands components. As battery 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, securing 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. When our maintenance plan is completed and tested, we’ll add here the maintenance schedule, video tutorials for all maintenance processes, and anything else we believe to be helpful.
VIDEO COMING OF: COMPLETE SOLAR MAINTENANCE – THIS TUTORIAL WILL SHARE OUR COMPLETE MAINTENANCE AND UPKEEP PROCESS FOR THE ONE COMMUNITY SOLAR SYSTEM
At one time, microgrids were only deployed in remote locations or at mission-critical facilities such as military bases or hospitals. Now though, due to several positive economic trends, increasing desire for energy independence and dependability, and a diversity of other reasons, microgrid development is proliferating. Employing distributed energy resources are now a cost-effective solution for many business and government organizations and the trends around technology and energy supply show the costs to build and operate distributed energy resources are rapidly decreasing. All signs point to increasingly advantageous economic conditions for microgrid owners for years to come and One Community will continue to support this through our open source resources sharing our experience installing, expanding, and maintaining our microgrids for the Duplicable City Center, Earthbag Village (Pod 1), the 6 villages to follow, and beyond.
Q: How are the generators sized?
Generators are sized using the maximum continuous wattage (power) they 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 is designed for the worst-case maximum load. This includes fuses, sizing wires, and busses to handle every possible device and appliance when simultaneously engaged. Even though this is a very unlikely scenario, it ensures the system will always work within 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 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 case of widespread battery failure?
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?
When possible all parts of the system are designed to fail in a way that provides the safest possible scenario for the remainder of the system and the system continues to provide power. This said, there could still be times when the only solution is to cut power completely. The details of this system of fail-safes depends on the environment where the system is placed and its particular construction and components.
Q: What systems are active in a power emergency?
In a power emergency only essential systems remain on. The following factors determine which systems are essential:
To obtain a better perspective of our energy needs, here is a chart showing how much specific components of One Community will contribute to peak wattage needs:
Now compare the above to the chart below that demonstrates how much specific components of One Community will contribute to total energy needs:
The importance of these charts shows components such as the heat pump, dryer, and water heaters draw the most power of the total daily needs because they run 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 simultaneously. The general trend remains that those items high on one chart are also high on the other chart, but the details vary and this is extremely helpful in understanding emergency power situations. Also, to conserve power, the hot tub (an excessive energy consumer) is designated as an item used only when surplus energy is available (summer months).
Q: How much biodiesel 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 initial working party of 20 we assume we are using approximately 4.2 kWh/day/ 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 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 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 resulting in a final value of 20 gallons per day for the average day.
Fuel storage on site is then divided by 20 gallons per day providing the number of days the fuel source sustains the party. The 100 kW generator with the 250 gallon base tank lasts the party about 12.5 days. For an entire month 620 gallons of fuel at today’s prices equates to $2,480 per month or $2,000 for off-road farm diesel.
Q: What are the benefits of bladder storage for fuel?
Storing biodiesel fuel in a large bladder is by far the most economical approach. However, bladders are flimsy, easily punctured, and cannot be buried, so they have to sit on the ground 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 require heavy equipment for underground placement.
Q: How long before batteries lose their charge?
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 are around 48 Volts. Knowing Volts x Amps = watts, we can determine the number of Amp hours needed:
Since we need that over the course of 60 hours:
If the largest battery size is 1000 Ah, then we require seven for this draw over 2.5 days.
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: What sets One Community apart from similar projects?
One Community's open source project-launch blueprinting strategy and the fact that we are open sourcing and addressing ALL elements of society simultaneously are a combination unique to our organization. Together, these will help others duplicate what we do and create self-propagating teacher/demonstration communities, villages, and cities capable of positively impacting every single person on this planet within one generation.
Q: What sets One Community's open source goals apart from similar projects?
To our knowledge, no other project exists that is providing the comprehensive nature and detail of everything we are open source project-launch blueprinting.
Q: What is the specific One Community short-term goal?
Q: What is the ultimate One Community long-term goal?
To transform our world into a sustainable and happier one through teacher/demonstration communities, villages, and cities to be built all over the world. We will work with these hubs as our open source partners and fellow leaders of the open source, Highest Good of All, and sustainable planet movement leading to a New Golden Age of cooperation, collaboration, innovation, creativity, sustainable living, and increased happiness for the entire human organism.
Q: How is One Community funded?
We are still seeking funding. Please see our Funding Related Details Page.
Q: Where will One Community be located and why?
Click HERE for property details that include why we have chosen the location we have.
Q: How far is One Community in the creation process?
Q: Why not just build a small-scale prototype home or community that includes a minimum-scale revenue-generating demonstration/operation? Wouldn't this get things going faster?
This already exists as Airbnb and people are doing amazing with it, so small-scale operations are not what we see as missing. What we see as missing is a complete model for self-sufficiency that is open source and reasonably replicable. Even complete models for self-sufficiency already exist in the form of the many eco-villages out there, what none of those offer though is any sort of understanding and/or path for how average people with average means can replicate them. We also think there isn’t enough of a compelling reason for most people to bother with changing how they live now to engage such a path/project, so our project is purposed to provide and demonstrate that too.
From a total global-change perspective though, we think it is even more important to create a permanent place dedicated to open source and capable of providing for the complete needs of hundreds of people working on open source creations full-time, with enough revenue generation and space for expansion to grow to over a 1000+ full-time volunteers while also being able to support the establishment of other open source teacher/demonstration/R&D hubs around the world. This is why the intended property, village models, and social architecture and economic focuses are all big.
To support faster and broader implementation while working on these big goals, we are also taking the extra time necessary to develop everything so it is modular and also implementable as individual components. This will allow for anyone who doesn’t desire the full teacher/demonstration hub approach to have options too, but our primary goal is to demonstrate the complete teacher/demonstration hub as easy enough, affordable enough, and attractive enough for average people with average means to want to replicate it and/or use what we provide to build their own version.
Q: If you are giving everything away through open source, how do you intend to make money?
Our model is designed to prosper specifically because we are giving everything away through open source project-launch blueprinting. We accomplish this through eco-tourism marketed with the open source infrastructure we have already created and other supported revenue streams outlined on our revenue streams page. All of this further promotes our model of spreading sustainability and actively promoting and distributing even more open source blueprints for duplication by as many people as possible.
Q: How will this help people in Third World countries and other areas where resources are needed most?
Using the four-phase strategy above, we wish to demonstrate building a teacher/demonstration community, village, and/or city as profitable for large investors and/or a way for small groups of people to pool what resources they have and get out of debt. We see this spreading and bringing resources to the areas that need them most because building these villages in these areas will be more affordable and easier to do with less building restrictions.
Q: How do you stop the model from being totally capitalized without the positive intent of the original model?
We are not focused on putting limitations on the use of everything we are creating because of our open source commitment. We will, however, directly support any organization contributing specifically to open source project-launch blueprinting and operating for The Highest Good of All.
Q: Where would I find a more detailed description of how this works?