4 ms·

I've got a somewhat goldilocks generator setup that involves a backfeed breaker (with mandatory interlock kit). I can run my central AC on this thing for ~5 hou

I've got a somewhat goldilocks generator setup that involves a backfeed breaker (with mandatory interlock kit). I can run my central AC on this thing for ~5 hours per 10 gallons of fuel. The generator is "portable" and rated for 12000 continuous watts. Its a bit of a pain to set up, but this is how I deal with multi-day hurricane scenarios living in the gulf coast region. I debated standby generator, but the cost vs value is a difficult argument considering how often the texas grid actually experiences a multi-day event. I am still considering something like a powerwall, but its a lot of extra crap to pay for and think about. My generator is properly winterized and will almost certainly start up if required to within the next half decade. Very simple.

adamfeldman 4y ago
How many tons is your AC? I’m also on the gulf coast and struggling to size a generator for my 5-ton compressor.
- bob1029 4y ago
  4 tons. 5 tons would definitely be pushing it on LRA/running amps for this size generator. But, this ultimately depends on the age & vendor of the compressor. Newer multi-stage or inverter compressor designs are much more likely to play well.
  - dijonman2 4y ago
    The opposite is often true with inverter driven compressors. It’s VFD powered which introduces harmonics and other noise from SWPS. In the data center industry you oversize your generators to deal with it. Plus dirty power from a struggling generator will kill the VFD. I just ran into this with my ECM condenser fan motor, circuit killed by generator.
    - bob1029 4y ago
      > The opposite is often true with inverter driven compressors. This is good to know. I had simply made an assumption - The inrush current is what I was primarily concerned with. I did not realize the other factors would cause trouble once it was ramped up to full speed. I can definitely see how dirty power from a cheap genset (like the one I have) could screw over a digital drive system.
itsoktocry 4y ago
>I can run my central AC on this thing for ~5 hours per 10 gallons of fuel. Sincere question, since I live in the opposite climate: how necessary is running your AC during a power outage? Where I'm from heat is a requirement during a winter storm outage, but my furnace backup doesn't require a ton power. I run most of my house on an 8000 watt portable generator.
- CapitalistCartr 4y ago
  Hurricanes are followed by the intense heat and humidity of Summer in the Gulf Coast. Without AC, it's miserable.
- bagels 4y ago
  In many places in California, you'll more likely die of the heat than die from cold.
- wil421 4y ago
  Where I live in The South it’s 80-90 degrees for months on end with 70-90% humidity. If you’re on the gulf coast a hurricane could knock you out for a while.
  - nicoburns 4y ago
    I guess it's the humidity that's the killer? 90F doesn't sound too bad for a few days. EDIT: This heat index (https://en.wikipedia.org/wiki/Heat_index https://en.wikipedia.org/wiki/Heat_index) puts 90F (32c) at 90% as equivalent to 122F (50c), in which case I can see the problem!
- bob1029 4y ago
  As others have noted, it is the humidity that is the killer. In most bad hurricanes, your home is going to leak some amount of water if you are in this region and take a direct hit. Doesn't matter how fancy your roof is. Something is going to leak. Absent some external miracles, your HVAC system is the fastest way to dry out your house after it gets absolutely wrecked in one of these storms. The only way, even. To be clear, my setup is for the aftermath. I am not expecting to ride through a hurricane with my portable genset sitting in the back yard chugging along.

adamfeldman 4y ago

How many tons is your AC? I’m also on the gulf coast and struggling to size a generator for my 5-ton compressor.

bob1029 4y ago
4 tons. 5 tons would definitely be pushing it on LRA/running amps for this size generator. But, this ultimately depends on the age & vendor of the compressor. Newer multi-stage or inverter compressor designs are much more likely to play well.
- dijonman2 4y ago
  The opposite is often true with inverter driven compressors. It’s VFD powered which introduces harmonics and other noise from SWPS. In the data center industry you oversize your generators to deal with it. Plus dirty power from a struggling generator will kill the VFD. I just ran into this with my ECM condenser fan motor, circuit killed by generator.
  - bob1029 4y ago
    > The opposite is often true with inverter driven compressors. This is good to know. I had simply made an assumption - The inrush current is what I was primarily concerned with. I did not realize the other factors would cause trouble once it was ramped up to full speed. I can definitely see how dirty power from a cheap genset (like the one I have) could screw over a digital drive system.

itsoktocry 4y ago

>I can run my central AC on this thing for ~5 hours per 10 gallons of fuel. Sincere question, since I live in the opposite climate: how necessary is running your AC during a power outage? Where I'm from heat is a requirement during a winter storm outage, but my furnace backup doesn't require a ton power. I run most of my house on an 8000 watt portable generator.

CapitalistCartr 4y ago
Hurricanes are followed by the intense heat and humidity of Summer in the Gulf Coast. Without AC, it's miserable.
bagels 4y ago
In many places in California, you'll more likely die of the heat than die from cold.
wil421 4y ago
Where I live in The South it’s 80-90 degrees for months on end with 70-90% humidity. If you’re on the gulf coast a hurricane could knock you out for a while.
- nicoburns 4y ago
  I guess it's the humidity that's the killer? 90F doesn't sound too bad for a few days. EDIT: This heat index (https://en.wikipedia.org/wiki/Heat_index https://en.wikipedia.org/wiki/Heat_index) puts 90F (32c) at 90% as equivalent to 122F (50c), in which case I can see the problem!
bob1029 4y ago
As others have noted, it is the humidity that is the killer. In most bad hurricanes, your home is going to leak some amount of water if you are in this region and take a direct hit. Doesn't matter how fancy your roof is. Something is going to leak. Absent some external miracles, your HVAC system is the fastest way to dry out your house after it gets absolutely wrecked in one of these storms. The only way, even. To be clear, my setup is for the aftermath. I am not expecting to ride through a hurricane with my portable genset sitting in the back yard chugging along.