Check the AI's Math - power requirements for a 20-person bugout location

[Todd]

I discovered the Open AI chat website the other day. So far it has helped me crystallize some general planning considerations, but it dived deep on this one...

Here's a copy/paste of the chat -

Question - Describe an off-grid power system for a 20-man base camp using AGM batteries and 200W solar panels. The power system has to power: 3 x 12v white LED strip lights for 4 hours per night, 1 x 12v red LED strip light for 8 hours per night, 2 x 40 litre 12v Waeco CF-40 fridge freezers for 24 hours a day, 1 x 240v 6-bay charger for Motorola XTS300 portable radios for 24 hours a day, 1 x 13.8v Xiegu G90 20W HF transceiver for 24 hours a day, 1 x 12v Panasonic CF-19 toughbook laptop for 24 hours a day, trickle charge 4 x 12v 20,000mah USB power banks for 24 hours a day.  What size batteries are required to accomplish this and how many batteries are required? How many 200W solar panels are required? What other components are required which haven't been mentioned above?

Answer - To power a 20-man base camp using AGM batteries and 200W solar panels, you will need the following components:

Batteries: To power the devices listed in the question, you will need a total of at least 400Ah of capacity at 12V. You can accomplish this with four 12V 100Ah AGM batteries, or with two 12V 200Ah AGM batteries.

Solar panels: You will need a total of at least 2kW of solar panel capacity to generate enough power to run all of the devices listed in the question. This can be accomplished with 10 200W solar panels.

Charge controller: You will need a charge controller to regulate the charge from the solar panels to the batteries. This will help to prevent overcharging of the batteries and extend their lifespan.

Inverter: You will need an inverter to convert the 12V DC power from the batteries to 240V AC power to run the 240V 6-bay charger for the Motorola XTS300 portable radios and the Panasonic CF-19 toughbook laptop.

Wiring and connectors: You will need a variety of wiring and connectors to connect the solar panels, batteries, charge controller, and inverter to each other and to the devices that you are powering.

Other components: You will also need a variety of other components such as fuses, circuit breakers, and switches to help protect the system and ensure that it is safe and reliable.

Overall, to power a 20-man base camp using AGM batteries and 200W solar panels, you will need at least four 12V 100Ah AGM batteries or two 12V 200Ah AGM batteries, 10 200W solar panels, a charge controller, an inverter, and a variety of wiring, connectors, and other components.

Question - describe how you calculated the above?

Answer - To calculate the size and number of batteries, solar panels, and other components needed to power a 20-man base camp using AGM batteries and 200W solar panels, I used the following information:

3 x 12V white LED strip lights for 4 hours per night: These lights will draw a total of 3 * 0.8A = 2.4A of current at 12V when they are on. Since they are on for 4 hours per night, they will use a total of 2.4A * 4h = 9.6Ah of capacity per night.

1 x 12V red LED strip light for 8 hours per night: This light will draw a total of 0.8A of current at 12V when it is on. Since it is on for 8 hours per night, it will use a total of 0.8A * 8h = 6.4Ah of capacity per night.

2 x 40 litre 12V Waeco CF-40 fridge freezers for 24 hours a day: These fridge freezers will draw a total of 2 * 3.5A = 7A of current at 12V when they are on. Since they are on for 24 hours a day, they will use a total of 7A * 24h = 168Ah of capacity per day.

1 x 240V 6-bay charger for Motorola XTS300 portable radios for 24 hours a day: This charger will draw a total of 8A of current at 240V when it is on. Since it is on for 24 hours a day, it will use a total of 8A * 24h = 192Ah of capacity per day.

1 x 13.8V Xiegu G90 20W HF transceiver for 24 hours a day: This transceiver will draw a total of 1.5A of current at 13.8V when it is on. Since it is on for 24 hours a day, it will use a total of 1.5A * 24h = 36Ah of capacity per day.

1 x 12V Panasonic CF-19 toughbook laptop for 24 hours a day: This laptop will draw a total of 3A of current at 12V when it is on. Since it is on for 24 hours a day, it will use a total of 3A * 24h = 72Ah of capacity per day.

Trickle charge 4 x 12V 20,000mah USB power banks for 24 hours a day: These power banks will draw a total of 4 * 0.1A = 0.4A of current at 12V when they are being trickle charged. Since they are being trickle charged for 24 hours a day, they will use a total of 0.4A * 24h = 9.6Ah of capacity per day.

Total capacity needed: 9.6Ah + 6.4Ah + 168Ah + 192Ah + 36Ah + 72Ah + 9.6Ah = 503.6Ah

To provide enough capacity to power all of these devices, you will need at least 400Ah of capacity at 12V. This can be provided by four 12V 100Ah AGM batteries, or by two 12V 200Ah AGM batteries.

To calculate the number of solar panels needed, I used the following information:

Each 200W solar panel will generate a maximum of 200W of power per hour when it is exposed to full sunlight.

The total power needed to run the devices listed in the question is 503.6Ah * 12V = 6043.2Wh per day.

To generate this much power, you will need at least 6043.2Wh / 200W = 30.2 hours of full sunlight per day.

To provide this much solar power, you will need at least 30.2 hours / 1 hour per panel = 30.2 solar panels.

To provide some margin for error, it is recommended to have a few extra solar panels, so you will need at least 35 solar panels to power a 20-man base camp using AGM batteries and 200W solar panels.

The amount of solar panels required seems excessive. We have previously run such a setup for 7 days with 5 x 100aH AGM batteries and 4 x 200W solar panels.

Is anyone able to check the AI's math and see if it checks out? I confused myself lol so thought I'd put the problem to the Brain's Trust here.

In case anyone's interested, here's the website I was using - https://chat.openai.com/

Cheers!

[Sir John Honeybucket]

Latitude has a definite impact on maximum solar power available, local unique weather after that. I wonder whether the AI can gather information based upon location , i/e regional solar surveys on the web or at least from a national 'heat  map' of averaged solar power potential?

Great idea using an AI to do these estimates for system parameters &etc.

-  Sir John Honeybucket

[Jackalope]

   Actual, real life loads will be less than what has been inferred by the AI.  For example, the fridge doesn't draw 7 amps continuously, there's a duty cycle involved.  The charge controller, type of batteries, and inverter will all have an effect on the overall system.  Start out with less panels and batteries, and add as needed; just make sure the charge controller and inverter are sized correctly.

[pkveazey]

Jackalope is right about power consumtion of things like Freezers and Refridgerators. They only draw power when the thermostat turns them on. A rule of thumb for a refridgerator is about 100 watts. It draws a lot more than that when it turns on and then a little more than that while its running and then zero when it turns off. Any device that uses a thermostat has to be averaged out in order to get anywhere near a correct load.

[JohnyMac]

Add to Sir John's latitude comment, angle of the panels to the seasonal sun position is important too.

Spring/Fall angle for my latitude is 45-degrees to the sun,
Summer, 70-degrees to the sun, and
Winter, 30-degrees to the sun.

Here is a link for you to determine what angle is best for your AO...  http://www.solarelectricityhandbook.com/solar-angle-calculator.html

[Todd]

Thanks for the detailed responses Gents.

As a writer, I spent a lot of time over the past few days playing with the AI chat doing everything from water requirements for a family of five for a six month period to creating an outline of a book to creating short stories to discussions about the World Economic Forum and whether its ultimate aim is to enslave Humanity in a techno-feudal nightmare existence.   

The AI is an impressive technology, but as this thread has proven, it's not infallible. In fact it's outright wrong in a lot of cases. When it doesn't have enough information for a detailed response it makes up its own parameters to fill in the gaps and quite often these go completely against the desired outcome. It's all about "the process" and not about the results - kinda like government.

The very idea of AI running factories or piloting aircraft or driving transport vehicles in the near future frightens the heck out of me. I don't trust it and no one else should either.

[grizz]

My take on it is to plan with no power, just like they did 1000 years ago. Sooner or later everything mechanical or electrical will fail just from simple use and replacement parts will not be available.

Humans have survived on this rock for millions of years without power or "stuff", thats what we need to start planning for.