Help with selecting an inverter to use

[Sion_the_Rapadant]

so I'm in the process of gathering what I need to setup a backup power system incase of a power outage. so far the means to charge the batterys has already already determined as well as what kind of battery. however when it comes to an inverter I'm not sure what I actually need. I do know that this system will need to run over 20 serer boxes each with roughly 1000watt PSUs, give or take. do I need it to match the added wattage of each PSU pluss a little more to be sure?

[it_dont_work]

What's the combined load of the a/c circuits all the servers are coming off, and is this backup powering besides the servers, or through the buildings local power?

[Sion_the_Rapadant]

I plan for it to be powering around 20,000 watts total at a given time, it will only be powering the servers. I plan to have the power source be a battery bank that is charged via solar panels and wind turbine but only feed off of it when the power goes out.

[it_dont_work]

Besides knowing your gonna need a few banks of multiple inverters and distribute batteries between them, rest is beyond me. I'd start by getting some advice from a professional, hopefully someone on ltt forums has a better idea. I'd probably start by working backwards from what the battery storage can provide safely, and weight that besides the time you want backup to run and how long, I doubt you'll need to provide 20,000watts constant, maybe at peak or 5% duty cycle. 

[Sion_the_Rapadant]

24 hours is the end goal, as for how many battery and weight I don't mind size nor how much it will cost. as for what they will safely output I have no idea

[it_dont_work]

Sorry I meant weigh as in total battery capacity to run the inverters for a given length of time. Your probably looking at an industrial power solution from a usp company, or something similar to what would feed a domestic property from a solar grid

[Sion_the_Rapadant]

I already looked into usps but I don't exactly have enough for one that would be big enough to power all of it. so instead I'm building one into my home. since the roof is large and will need to be redone I'll be using solar panel shingles on as much surface area as I can. the wind turbines being placed on the balcony and the top of the fence posts. as for where the batterys will be stored I'm going to construct a large shed like building that will be stocked full as I can make it. as far as hooking them up I got all that down. I really just need to know if I need to match the total watts from there I should be good. its just this part stumping me.

[W-L]

21 hours ago, Sion_the_Rapadant said:

-SNIP-

As mentioned you most likely won't require that much wattage, and if you do will definitely not be able to keep things running for 24 hours as the bank of batteries for something like that would be enormous. You would be talking dozens of server racks just full of batteries. What exactly are you powering we can get a better idea of something that can be done either DIY or commercially available. 

[Sion_the_Rapadant]

nothing atm, I'm currently gathering what I'll need to run all this. at the moment I'm simply laying out the plan for it. as for the battery bank size its not of much concern. each server I'll have running will be about 1000w give or take 100w. there will eventually be alot more then 20 servers but at the beginning I'll be starting at 20. if not 24 hours worth of storages 12 then?

[W-L]

Just now, Sion_the_Rapadant said:

nothing atm, I'm currently gathering what I'll need to run all this. at the moment I'm simply laying out the plan for it. as for the battery bank size its not of much concern. each server I'll have running will be about 1000w give or take 100w. there will eventually be alot more then 20 servers but at the beginning I'll be starting at 20. if not 24 hours worth of storages 12 then?

It would be a much better idea for each server to have their own independent UPS system, and really large battery bank  for each one if you require extended run time than one huge one. Just to give you an idea at full load very few UPS's can sustain power for more than a few mins as they are more designed as a system for safely shutting down the systems.  

 

If it's just storage servers they wouldn't be using that much power unless they are in the middle of rendering or processing something. 

[Sion_the_Rapadant]

they will be server boxes that I'll be renting out, so they will likely have constant usage. I'm also going to be using a pfsense router to connect many WANs together for massive bandwidth to support it all. Cant have an angry client mad about down time.

[JokerProduction]

I think this is a pipe dream.  There is so much i don't think you've considered.

 

Just to give you an idea to provide a continius 20kw load for 24hours would require at least 480 truck batteries.  These batteries have to be changed every 4 years.  And while car batteries can be used sealed batteries are the norm otherwise ventilation becomes very important.

 

Also its impossible for us to recommend an inverter when we dont know your requirements on voltage and phases.

 

Generally it would be a better idea to get a smaller commercially available ups and a seperate back up generator for backup power it will be much cheaper

 

Also i'm assuming you dont have an engineering degree nor gonna have it designed proffesionaly since you are asking some basic questions.  You might want to check with you insurance company and see how they like having un certified electrical equipment in your residence and how it will affect your premiums if they will even insure it at all.

 

 

 

[Sion_the_Rapadant]

I won't be paying for insurance. as for voltage and phases, I have no idea on that. for the batterys I'll be using deep cycle batterys(voltage and number pending the inverter used). on ventilation it won't be much of an issue since I'll be building the area it will be stored in.

[JokerProduction]

Its your load that dictates what kind of inverter you need.  Does the equipment run 120v single phase,  240v 1ph ,208 3 ph ,480 3ph?  Generally a 3ph inverter will be cheaper.

 

Also i would check against local building codes and make sure your even allowed to have a battery charging room in a residential area.  Where i live it is allowed but requires you to install a monitored fire alarm system and have fire suppression installed

 

What size is the electrical service at the residence?

[Sion_the_Rapadant]

its commercial property, it just happens to have a house built on it from before rezoning happened. I'm guessing the house runs on either 120 or 240. which ever one is the 3 prong sockets, not real sure atm. but seeing as the property will be undergoing renovations before this I'd likely upgrade the electrical. for the server equipment I'll be using regular atx power supplies most likely.as to laws on fire suppression all I'm required is a fire extinguisher for each kind of fire hazard.

[W-L]

Just now, Sion_the_Rapadant said:

its commercial property, it just happens to have a house built on it from before rezoning happened. I'm guessing the house runs on either 120 or 240. which ever one is the 3 prong sockets, not real sure atm. but seeing as the property will be undergoing renovations before this I'd likely upgrade the electrical. for the server equipment I'll be using regular atx power supplies most likely.as to laws on fire suppression all I'm required is a fire extinguisher for each kind of fire hazard.

Ok in a commercial property I think you will be ok since you were wanting to pull 20kW in a residential property that would be an issue as you would be using more than half the capacity that you can draw in a residential line. 

[Sion_the_Rapadant]

the property zone is commercial but the house is still on residential power. but it will need an upgrade regardless. still using some really old wiring. like 40+ yrs old but that will be fixed

[W-L]

15 minutes ago, Sion_the_Rapadant said:

the property zone is commercial but the house is still on residential power. but it will need an upgrade regardless. still using some really old wiring. like 40+ yrs old but that will be fixed

Yeah if you were to do something like this I would check with your electrical provider to see if they can put in a new line or have an electrician put in a separate sub panel to the house. Going back to the backup power though I would recommend to go with individual UPS units per server if you want to try and set something like this up. 

[Sion_the_Rapadant]

are there ways I could use the solar paneling and wind turbine to charge the batterys in them? I'd like to have an alternative means of charging incase of a power failure lasting more then a few hours if possible.

[W-L]

2 minutes ago, Sion_the_Rapadant said:

are there ways I could use the solar paneling and wind turbine to charge the batterys in them? I'd like to have an alternative means of charging incase of a power failure lasting more then a few hours if possible.

I wouldn't recommend it since the number of panels needed would be huge, you would be better off with a backup generator to kick in if you really need serious power. The UPS's wouldn't be simple to modify as you need to configure it to only kick in during extended power outages among other things as the UPS's already have built in charge circuity. 

[Sion_the_Rapadant]

it would be a rather large roof, the whole property is actually to buildings that are apartments. I'd be using solar panel shingles so I'd have the surface area of too whole roofs plus the wind turbines(its rather windy in the area so I thought it would be helpful) as for a generator that may not be an option.

[W-L]

3 minutes ago, Sion_the_Rapadant said:

it would be a rather large roof, the whole property is actually to buildings that are apartments. I'd be using solar panel shingles so I'd have the surface area of too whole roofs plus the wind turbines(its rather windy in the area so I thought it would be helpful) as for a generator that may not be an option.

For that it would be more complex if you were to do individual UPS units per server but that is still ideal for safe shutdown if there is an extended power outage. You may want to look into cold redundant or DC to DC PSU's if you have a separate solar array backup. 

[Sion_the_Rapadant]

so one psu connected to the psu and a second one that is a backup connected to the solar battery bank then right? wouldn't I still need an inverter or not?

[W-L]

1 minute ago, Sion_the_Rapadant said:

so one psu connected to the psu and a second one that is a backup connected to the solar battery bank then right? wouldn't I still need an inverter or not?

It depends, there are cold redundant PSU's that can take both AC or DC through the same IEC connector so it depends on the system you want in place but personally I would still recommend to go with proper UPS's per server since they can manage each one individually where an inverter system wouldn't be able to do so. 

[Sion_the_Rapadant]

ah, thx for the help ^^.