Subjective listening impressions of alternate power (solar, generator, battery)

[austinpop]

After living through the Texas storms of Feb 2021, where I lost grid power for a total of 126 hours in a 7-day period, with the largest outage lasting 65 hours, I am — like many — looking at resiliency options. These include a combination of:

• Solar panels
• Battery packs like the Tesla Powerwall 2
• Backup generators like the Generac.

 

Obviously, the driving force here is resiliency to extended grid outages, but as an audiophile, another important concern is the impact on SQ. Today, I am getting "clean" grid power — I know, this is funny given grid power is hardly clean! However, all of the alternate power solutions involve the use of inverters to convert DC to AC. These inverters are usually integrated with the specific solution chosen, and it's unclear if they produce anything close to a sine wave. Solar panels have the additional choice of micro-inverters at each panel vs. a single system-wide inverter, but this is a second order detail.

 

The larger questions are:

• Do grid-alternative power sources negatively (or positively) impact the SQ of a high-end audio system?
• And can this be mitigated by the use of a power line conditioner — pick your favorite?

 

Please share your subjective listening impressions if you have gone through this. Does your alternate source sound better/worse/equal to the grid? What lessons did you learn?

 

I found it timely (and troubling) to watch Mikey Fremer's video on the Ask Paul video series (https://www.psaudio.com/askpaul/mikey-fremer-vs-ask-paul/) where he talked about SQ loss due to the installation of a transfer switch for a backup generator. 🤦🏽‍♂️

 

Please share your findings.

[austinpop]

Interesting! I don't think I have the land area and topography on my lot for that, but did not even realize that was an option.

[austinpop]

8 minutes ago, Jud said:

The very best inverters have harmonic distortion and power factor approximately equivalent to what the utility is usually required by law to provide you.  Do not expect an SQ improvement from being off-grid.

 

I will be ecstatic if I experience no degradation. An improvement would be exceeding expectations.

 

8 minutes ago, Jud said:

Also don't forget that generators can be noisy, so I wouldn't go that route

 

If I go the generator route, I would not be looking to run audio on generated power. In this scenario, my main concern would be the audio degradation of the transfer switch.

 

I just saw Paul McGowan has posted a response on the PS Audio forum, where he points the finger at automated transfer switches. See https://www.psaudio.com/askpaul/mikey-fremer-vs-ask-paul/#comment-192266

 

That's a fair point, and I see no issue just using a manual transfer switch as a way to avoid this.

[austinpop]

1 hour ago, Jud said:

 

On the other hand, if you used solar panels and batteries, you could enjoy listening to music when the grid went down.  🙂

 

The irony for me is that my grid cost is quite low. Our utility is still regulated, so does not have time of use rates, and energy costs in TX are low. So going to solar and battery, while environmentally and technologically appealing, is an economic tough sell.

 

It would take me over 20 years to break even on solar + battery, even if I paid cash for the system. Even if I subtracted out the cost of a generator backup, it would still take 13 years to break even.

 

Anyway, let's not digress: I want to keep the focus on SQ benefit or degradation.

[austinpop]

30 minutes ago, Jud said:

 

If you don't plan to run audio on generated power, then you are essentially just asking about the audio effect of a transfer switch.  Then perhaps the simplest solution would be to exempt a separate audio circuit from the transfer switch, if things can be wired that way.

Indeed.

 

But I do want to hear about solar and battery installations. 
 

A couple of friends who have solar PV installs without battery sent me their experiences. Both have Sunpower panels with micro inverters. Two experiments were reported:

 

- friend 1 compared SQ during the day, when the panels were supplying power, to the night, when power was from the grid. They observed no noticeable difference.

 

- friend 2 ran an experiment during the day. First with panels providing power. He then disabled the panels via a switch, and compared SQ to grid power. He felt the grid SQ was a tick better, but not night and day (pun intended)!

[austinpop]

10 minutes ago, acg said:

@austinpop

 

I will be moving soon to off-grid for my office which also includes my playback system.  Different country and different mains issues but it will be solar into LiFePO4 batteries which feed voltage into the system via a 240V Victron inverter (Victron simply because Living Voice use them in their battery power systems, and because they are very good quality).  Following that inverter I have had a very knowledgeable and experienced fellow in this field wind an enormous balanced isolation transformer with an inductive AC filtering system which should improve sound quality above and beyond the already decent mains system I have here.

 

The first bits have been picked up by the courier today and if you like I can update you with what I end up with.

Please do! Keep us posted. 

[austinpop]

1 hour ago, sdolezalek said:

and decided to go with larger inverters rather than on-panel microinverters

 

I realize your choices are from 10 years ago, but welcome any inverter recommendations that are audio friendly.

 

One upside of micro-inverters, as I understand it, is that it isolates the energy output of each panel. So if one panel is in shade, it does not affect the output of the other panels. Apologies if I have this wrong, I am still in research mode.

[austinpop]

22 minutes ago, JoeWhip said:

We have a 27 kw whole generator from Generac. Special attention was made to properly grounding the system. There is no difference in SQ pre and post install and while the generator is running. I have listened to music for hours with it before the power came back. No experience with solar. Checked into with Tesla. Due to the terrain here they told us not to bother as we would basically get nothing in the winter months.

Great data point, Joe. Thanks.

 

I’m assuming you have this infamous auto-transfer switch?

 

And could you elaborate on grounding considerations with the generator?

[austinpop]

1 hour ago, JoeWhip said:

Natural gas, the line out of the meter was split, one to the inside and one to the generator.  You can hear it in the audio room but it is not very loud with the windows closed. It is two levels above the ground level of the house. The space is fully insulated and is 4 years old now.

Can it take propane as an alternative, if you lose natural gas, for some reason?

[austinpop]

1 hour ago, lmitche said:

Following this incident, I swore I would buy a whole house, natural gas generator. Unfortunately I was not alone, and it was months before even an appointment with a salesman was available. Later a quote for a $15,000 installation was obtained. I passed, the $1000 solution was really all that was necessary.

 

The portable generator sits in the garage today, unused since the hurricane, drained of oil and gas.  Will it start if needed again? IDK, but I like having it there.

 

29 minutes ago, JoeWhip said:

We bought a gasoline generator too after Sandy. Filling it every few hours with gas in the rain and wind and running cords through open windows was a PITA. Doing that in winter with a snow or ice storm, no way. Yes the whole house generator was expensive but it has worked like a charm and it operates instantaneously and I don’t have to get off the couch. Worth every penny.

You both have perfectly stated the dilemma I am now on the horns of.

 

Since I’m not as handy as Larry’s solution would require, the low-cost alternative I’m contemplating is to have an electrician install a manual transfer or interlock switch, identify the breakers we would use in an outage, and then buy an LPG portable generator and a few tanks of propane, that could be wheeled out if and when  needed.

 

But the whole house system is very appealing too. I will also have to wait a few months to get a quote, due to the insane demand.