<instructions>Your goal is to analyze the following comment and estimate how highly it will be upvoted by the Hacker News community.</instructions><comment><author>rsync</author><text>&amp;quot;To do this, a switch needs to physically disconnect the utility meter from the main loads panel ... this is the hard part.&lt;p&gt;It doesn&amp;#x27;t need to be.&lt;p&gt;You can just use a physical interlock and toggle between utility breaker and (any input you want) breaker.&lt;p&gt;You can do this on an integrated meter panel.&lt;p&gt;This is a dead-simple configuration that you can comprehend - and verify - with your own eyes.&lt;p&gt;The lock-out switch is NEC compliant, utility approved, etc.:&lt;p&gt;&lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.amazon.com&amp;#x2F;Generator-Interlock-Compatible-Homeline-SD200SA&amp;#x2F;dp&amp;#x2F;B0BZCHNM3Y&amp;#x2F;&quot; rel=&quot;nofollow noreferrer&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.amazon.com&amp;#x2F;Generator-Interlock-Compatible-Homeli...&lt;/a&gt;&lt;p&gt;Yes, you do lose all power for a second or two but ... so much simpler and comprehensible than an ATX solution.</text><parent_chain><item><author>s_tec</author><text>I recently installed an Enphase home backup system as a DIY project (crazy, I know). The biggest problem with any home-backup system is moving the loads onto their own sub-panel. When the utility goes down, power needs to flow into the home, but &lt;i&gt;not&lt;/i&gt; to the rest of the neighborhood. To do this, a switch needs to physically disconnect the utility meter from the main loads panel. If this isn&amp;#x27;t possible (such as when the meter is integrated into the panel), all the loads need to move to a sub-panel. This is the hard part.&lt;p&gt;Once the meter and main panel are separate, the various backup solutions become pretty similar. The disconnect switch installs between the two, with the solar and battery attached. Sometimes the disconnect switch + solar + battery are all in one unit (like the Bluetti EP900), while sometimes the solar inverter, battery, and switch are all separate units (like Tesla or Enphase). The Tesla switch and battery are sleek &amp;amp; glossy, but the inverters are ugly. The Enphase stuff isn&amp;#x27;t quite as shiny, but at least the boxes look consistent.&lt;p&gt;Performance-wise, the systems seem pretty similar as well. Most systems are around $10K for 10KWh of capacity, with somewhere around 6-9 KW of peak discharge rate. I imagine these prices will drop a lot over the next decades. If the battery becomes obsolete, just install a different system. Once the home is correctly wired, swapping the storage system should be pretty straightforward.</text></item><item><author>rndmize</author><text>This is something I&amp;#x27;ve been curious&amp;#x2F;interested in for a long time, so its good to see that somewhere out there (random Pacific islands aside), there&amp;#x27;s communities making it work.&lt;p&gt;Some rough numbers I did a month or two ago - Tesla offers a megapack that has 3.9 MWh at a cost of $2.4m. &amp;quot;In 2021, the average annual electricity consumption for a U.S. home was 10,632 kilowatt-hours (kWh). Or about 886 kWh per month.&amp;quot; That&amp;#x27;s about 30 kWh per day; my community has 45 houses, so use of 1.35 MWh in total, so a megapack will provide power for 3 days for the community at a cost of ~50k per house. Probably not worth it and I&amp;#x27;d expect 3 days to be overkill. But a community that was double our size will have a cost of about 25k per unit for 1.5 days of power - which doesn&amp;#x27;t sound too bad to me.&lt;p&gt;Another thing I&amp;#x27;ve found interesting is Anker seems to be getting into the home power business - &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.anker.com&amp;#x2F;anker-solix&amp;#x2F;home-energy-solutions?ref=anker-solix-brand&quot; rel=&quot;nofollow noreferrer&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.anker.com&amp;#x2F;anker-solix&amp;#x2F;home-energy-solutions?ref=...&lt;/a&gt; - which I&amp;#x27;m hopeful about, since it doesn&amp;#x27;t seem like anyone except Tesla has been able to make something that feels simple&amp;#x2F;easy&amp;#x2F;attractive. Every time I&amp;#x27;ve look at Powerwall alternatives I&amp;#x27;m been unimpressed by the offerings; maybe Anker can deliver.</text></item></parent_chain></comment><story><title>Developers are building communities that act as their own miniature power grids</title><url>https://www.nytimes.com/2023/08/07/realestate/microgrid-solar-power-energy.html</url></story>
<instructions>Your goal is to analyze the following comment and estimate how highly it will be upvoted by the Hacker News community.</instructions><comment><author>bombcar</author><text>You don&amp;#x27;t move the loads to the sub panel. You make a new main panel, move the feed to that, and turn the old main panel into a sub panel. Much easier.</text><parent_chain><item><author>s_tec</author><text>I recently installed an Enphase home backup system as a DIY project (crazy, I know). The biggest problem with any home-backup system is moving the loads onto their own sub-panel. When the utility goes down, power needs to flow into the home, but &lt;i&gt;not&lt;/i&gt; to the rest of the neighborhood. To do this, a switch needs to physically disconnect the utility meter from the main loads panel. If this isn&amp;#x27;t possible (such as when the meter is integrated into the panel), all the loads need to move to a sub-panel. This is the hard part.&lt;p&gt;Once the meter and main panel are separate, the various backup solutions become pretty similar. The disconnect switch installs between the two, with the solar and battery attached. Sometimes the disconnect switch + solar + battery are all in one unit (like the Bluetti EP900), while sometimes the solar inverter, battery, and switch are all separate units (like Tesla or Enphase). The Tesla switch and battery are sleek &amp;amp; glossy, but the inverters are ugly. The Enphase stuff isn&amp;#x27;t quite as shiny, but at least the boxes look consistent.&lt;p&gt;Performance-wise, the systems seem pretty similar as well. Most systems are around $10K for 10KWh of capacity, with somewhere around 6-9 KW of peak discharge rate. I imagine these prices will drop a lot over the next decades. If the battery becomes obsolete, just install a different system. Once the home is correctly wired, swapping the storage system should be pretty straightforward.</text></item><item><author>rndmize</author><text>This is something I&amp;#x27;ve been curious&amp;#x2F;interested in for a long time, so its good to see that somewhere out there (random Pacific islands aside), there&amp;#x27;s communities making it work.&lt;p&gt;Some rough numbers I did a month or two ago - Tesla offers a megapack that has 3.9 MWh at a cost of $2.4m. &amp;quot;In 2021, the average annual electricity consumption for a U.S. home was 10,632 kilowatt-hours (kWh). Or about 886 kWh per month.&amp;quot; That&amp;#x27;s about 30 kWh per day; my community has 45 houses, so use of 1.35 MWh in total, so a megapack will provide power for 3 days for the community at a cost of ~50k per house. Probably not worth it and I&amp;#x27;d expect 3 days to be overkill. But a community that was double our size will have a cost of about 25k per unit for 1.5 days of power - which doesn&amp;#x27;t sound too bad to me.&lt;p&gt;Another thing I&amp;#x27;ve found interesting is Anker seems to be getting into the home power business - &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.anker.com&amp;#x2F;anker-solix&amp;#x2F;home-energy-solutions?ref=anker-solix-brand&quot; rel=&quot;nofollow noreferrer&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.anker.com&amp;#x2F;anker-solix&amp;#x2F;home-energy-solutions?ref=...&lt;/a&gt; - which I&amp;#x27;m hopeful about, since it doesn&amp;#x27;t seem like anyone except Tesla has been able to make something that feels simple&amp;#x2F;easy&amp;#x2F;attractive. Every time I&amp;#x27;ve look at Powerwall alternatives I&amp;#x27;m been unimpressed by the offerings; maybe Anker can deliver.</text></item></parent_chain></comment><story><title>Developers are building communities that act as their own miniature power grids</title><url>https://www.nytimes.com/2023/08/07/realestate/microgrid-solar-power-energy.html</url></story>