CH.ESC · EL SEGUNDO · FIELD GUIDE · AS OF SEP 21, 2026

Small solar, for here.

Four rungs from one panel on a desk to a block that shares a battery. Built from used panels and listed parts, nothing custom. Storage sized to the night, not to the roof. Five ways to move the power, ranked by how much friction each one buys. A local network that is not the internet, for the phones and laptops the block already owns. Then the shelves: where to actually buy it, and what the rules said on the day we checked.

the laddersize itstoragemoving powerthe meshwhere to buyrules & moneylearnmethod

6.1peak-sun hours a day, year average at LAXPVWatts v8, station 1.7 km from LAX, seen 2026-09-21 · pvwatts.nlr.gov ↗
1,700kWh a year per installed kW, fixed south roofsame run, 20° tilt, 14% losses: 4.6 kWh a day per kW · pvwatts.nlr.gov ↗
26–55¢per watt for new panels at wholesale desksLongi 380 W at 26¢, Znshine 440 W at 37¢, REC 460 W at 55¢, seen 2026-09-21
$234–287per kWh for a UL-listed 48 V rack batterySOK on sale and EG4 LifePower4 V2 at list, seen 2026-09-21

THE LADDER · FOUR RUNGS · EVERY PART NAMES A SHELF

Climb by adding, not replacing.

RUNG 00

Pocket

One panel, one box, no wires past the desk.

Budget
$150–$300
Panels
100 W–200 W
Storage
0.25–0.6 kWh · 12 Va 12 V 20–50 Ah LiFePO4 drop-in, or a small portable power station
Yield
0.4–0.9 kWh a day
Runs
lights, phones, a laptop, a router or a mesh node
Permit
none

PARTS

CLIMB Almost nothing carries up. Treat this rung as tuition, or buy a portable power station instead and it becomes the sneakernet battery on rung three.

RUNG 01

Shed

Four used panels and a battery that runs a fridge.

Budget
$700–$1.5k
Panels
400 W–800 W
Storage
2.5–5 kWh · 24 V or 48 V24 V 100–200 Ah, or a single 48 V 100 Ah rack battery if you already know you are climbing
Yield
2–4 kWh a day
Runs
a fridge, laptops, cordless-tool charging, an e-bike, a commons hub and a LoRa relay
Permit
none while it stays a plug-in cord to portable loads; no hardwiring

PARTS

CLIMB Buy 48 V-capable gear here and every part survives to the house rung. 12 V gear hits a wall around 1 kW of inverter.

RUNG 02

House-critical

The loads you would miss in an outage, on their own panel.

Budget
$3k–$6k
Panels
2 kW–3 kW
Storage
5–10 kWh · 48 Vone or two 48 V 100 Ah server-rack batteries
Yield
9–14 kWh a day
Runs
fridge and freezer, internet, lights, a few outlets, a heat-pump water heater on a good day
Permit
yes: anything hardwired to the house needs a City of El Segundo electrical permit and a licensed electrician; a transfer switch or critical-loads subpanel is the safe shape

PARTS

CLIMB Add strings and batteries in parallel. Nothing gets replaced, which is the whole point of picking 48 V two rungs ago.

RUNG 03

Block

Several roofs, one shared battery, a hub that stays on.

Budget
$15k–$40k
Panels
10 kW–20 kW
Storage
30–60 kWh · 48 V, several cabinetspooled rack batteries at the hub, plus portable stations that travel
Yield
45–90 kWh a day
Runs
a shared cold room, a comms hub, EV top-ups, the resilience site for a few streets
Permit
yes, and interconnection with Southern California Edison if anything can export; the sneakernet variant needs neither

PARTS

CLIMB Start this rung as a sneakernet: charge portable stations at the best roof, carry them to where power is needed. Wire the bus only after the pattern proves itself.

SIZE IT · EL SEGUNDO SUN · 6.1 PEAK-SUN HOURS · 76% SYSTEM EFFICIENCY

Tick what has to stay on. The page does the arithmetic.

LOADS · kWh A DAY
DIALS
DAILY LOAD2.5kWh
PANELS550W
BATTERY2.5kWh
LANDS ONRung 01 · Shedsee the rung ↑

Store one to one and a half days of the loads you actually need after dark. Most people overbuy the battery and underbuy the panels. The 76% system efficiency is PVWatts' own default losses plus the inverter, so these are the numbers the sun leaves you, not a brochure. Worked example: a fridge and the internet, 1.6 kWh a day with 1.0 of it at night, wants 350 W of panels and a 1.7 kWh battery. That is the shed rung.

STORAGE · SIZE TO THE NIGHT, NOT THE ROOF

One chemistry to buy. Three kinds of storage that cost nothing.

BUY THIS

LiFePO4

Safe indoors, 3,000 to 6,000 cycles, flat under load, and roughly $150 to $250 per kWh for a listed pack. Look for UL 1973 on rack batteries and a BMS with a low-temperature charge cutoff.

WATCH

Sodium-ion

Cheap and rugged, fine in cold, lower energy density. Worth pricing for the block rung by 2027, not worth waiting for on the small rungs.

ONLY IF FREE

Lead-acid

Half the usable capacity, a fifth of the cycle life, vents hydrogen. If someone gives you a set, use it outdoors and plan its replacement.

BUY FOR RUNGS ZERO AND THREE

Portable power stations

A battery, inverter, MPPT and sockets in one UL-listed box. Costs more per kWh than a rack battery, needs no wiring or permit, and it carries. That last fact is what makes the block rung possible without trenching.

STORAGE THAT IS NOT A BATTERY

TimingRun the dishwasher, laundry and e-bike charger on timers during sun hours. The battery only carries the night. This is the cheapest storage that exists.
A chest freezerFill the spare space with water jugs, let the inverter run it hard midday, and it coasts through the night on frozen mass.
Hot waterA DC heating element or a smart relay dumps surplus panel output into the tank instead of curtailing it. A heat-pump water heater on a timer is the same trick at three times the efficiency.

MOVING THE POWER · FIVE WAYS · CLIMB ONLY AS FAR AS YOU NEED

Each step adds reach and adds friction.

1

No wires

REACH · THE DESK FRICTION · NONE

The loads live where the panel is. Rung zero needs nothing from anyone.

2

A 48 V DC bus and PoE

REACH · A ROOM OR A YARD FRICTION · LOW

Run 48 V DC to fixed loads and use Power over Ethernet for mesh radios, cameras and small computers. USB-C PD adapters hang off the same bus. Under 60 V DC is generally treated as low voltage, which means far less permitting friction. Confirm with El Segundo Building Safety before it goes through walls.

3

Battery sneakernet

REACH · A FEW STREETS FRICTION · NONE

Charge portable stations at the sunniest roof and carry them to where the power is needed. Zero wiring and zero permits. For a block this works better than it sounds, and it is how rung three should start.

4

An AC island

REACH · THE HOUSE FRICTION · PERMIT + ELECTRICIAN

An inverter feeds a critical-loads subpanel through a transfer switch. Once anything is hardwired to the house you need a permit and a licensed electrician. Never backfeed a panel without a transfer switch. It can kill a line worker.

5

The grid

REACH · EVERYONE FRICTION · INTERCONNECTION

Under NEM 3.0 the utility pays a fraction of retail for exports, so grid-tie without a battery barely pays. Anything that can export needs Southern California Edison interconnection. Plug-in solar is legal in Utah; California's rules are moving, so check the rules shelf before assuming.

THE LOCAL NETWORK · NOT THE INTERNET · 4 LAYERS · PHONES, LINUX, LAPTOPS

A network that stays up when the wire goes down.

The internet is a wire someone else owns. A local network is the same phones and laptops talking to each other over the air, and it runs on the same small solar as everything else on this page. Three layers, cheapest first. Each one works on its own; together they cover a block.

LAYER 1

Phone to phone, no hardware

REACH · A ROOM, A COURTYARD, A QUEUE

Apps that use Bluetooth and Wi-Fi Direct to pass messages from phone to phone, hopping through whoever is in range. Nothing to buy, nothing to install on a roof. iPhones and Androids do not always see each other, so pick one app the whole block agrees on.

Cost
free, apps only
Power
the phone you already charge
iPhone
yes: Bitchat, Berty, OSHI. Not Briar, not Meshenger
Android
yes: all of them
Linux
OSHI only
Rung
pocket ↑

LAYER 2

LoRa mesh nodes

REACH · A FEW MILES LINE OF SIGHT, A MILE THROUGH HOUSES

Pocket radios on the license-free 915 MHz band that carry short text and positions between phones over miles, hopping node to node. A node runs for days on a small battery and forever on a palm-sized panel. Every phone pairs to a node over Bluetooth with a free app. This is the layer that reaches the whole block for the price of a dinner each.

Cost
$27–$101 a node
Power
0.04–0.5 W a node
iPhone
yes: the Meshtastic and MeshCore apps, paired to a node over Bluetooth
Android
yes: Play and F-Droid
Linux
yes: CLI, web client, runs a node
Rung
pocket ↑

LAYER 3

A Wi-Fi commons

REACH · A HOUSE, A YARD, A STREET WITH ROOF LINKS

A router with no wire in the back and a small computer beside it. Phones join the network the way they join any Wi-Fi, and instead of the internet they find a local page, a shared drive, offline Wikipedia and a chat room. Roof radios link one commons to the next. This is where a copy of PointCast could live when the wire is gone.

Cost
$30–$600 a node
Power
3–10 W a node
iPhone
yes: stays joined to a no-internet Wi-Fi; grant Local Network permission
Android
yes
Linux
yes, and it runs the hub
Rung
shed ↑

LAYER 4

One fabric over all of it

REACH · WHEREVER THE LAYERS TOUCH

Software that treats LoRa, Wi-Fi, Bluetooth and a stray internet link as one encrypted network, so a message typed on the commons reaches a LoRa node three roofs away. Runs on a Pi or a laptop, free.

Cost
free, apps only
Power
the phone you already charge
iPhone
TestFlight beta only, no App Store client yet
Android
yes: Sideband APK, no Play listing
Linux
yes: Sideband, MeshChat, rnsd on a Pi
Rung
shed ↑

THE APPS · WHAT RUNS ON WHAT · CHECKED SEP 21, 2026

LAYER 1 · bitchat.free Bitchat Bluetooth mesh chat with no accounts and no phone numbers, up to a handful of hops, encrypted with the Noise protocol. Version 1.7 on the App Store when seen. No outside security audit yet. iOS 16+macOSAndroid 8+ SEEN 2026-09-21 LAYER 1 · berty.tech Berty Bluetooth, local Wi-Fi and Apple Multipeer under an encrypted-by-default protocol from a Paris non-profit. Alive and shipping; its own README says not yet for sensitive data. iOSAndroid SEEN 2026-09-21 LAYER 1 · oshi-messenger.com OSHI Bluetooth and Wi-Fi Direct mesh with a Linux desktop client, LoRa radio support and an optional relay. Version 1.0, small and new: treat as unaudited. iOSAndroidWindowsLinux SEEN 2026-09-21 LAYER 1 · briarproject.org Briar The veteran: Bluetooth, local Wi-Fi and Tor, everything stored on the phone. Android only, and the developers say no iPhone client is planned. In maintenance mode since July 2026, security fixes only. Android SEEN 2026-09-21 LAYER 1 · bridgefy.me Bridgefy Bluetooth mesh with the Signal protocol. The catch for an outage: it needs the internet to log in, and reviewers report being logged out when the wire is gone. iOS 16.6+Android SEEN 2026-09-21 LAYER 2 · meshtastic.org Meshtastic The open LoRa mesh: AES-256 channels, phones paired over Bluetooth, a web client and a flasher in the browser, a Python CLI for a Pi. The ground range record is 331 km. SoCal Mesh runs on it with non-default settings, see the groups. iOSAndroidF-DroidwebLinux CLI SEEN 2026-09-21 LAYER 2 · meshcore.co.uk MeshCore The younger LoRa mesh with companion, repeater and room-server roles and an open-source client on every platform. Fifty-plus boards including the Heltec V3 and the T-Deck. RegionMesh runs Los Angeles on it. iOS 13+AndroidwebLinuxmacOSWindows SEEN 2026-09-21 LAYER 2 · reticulum.network Reticulum and RNode The encrypted network stack that makes a LoRa radio, a Wi-Fi link and a stray internet connection one fabric. RNode firmware turns the same Heltec, LILYGO and RAK boards into Reticulum interfaces. Layer four lives here. Android APKLinuxmacOSWindowsiOS TestFlight SEEN 2026-09-21 LAYER 4 · github.com Sideband The Reticulum messenger: sideloaded on Android, an AppImage or pip on a Pi. No app-store listing. The iPhone build is a TestFlight beta that only networks in the foreground. Android APKLinuxmacOSWindows SEEN 2026-09-21 LAYER 4 · github.com Reticulum MeshChat A web page on the commons that is a chat room, a file drop and voice over Reticulum. Phones use it in a browser, which is how iPhones get on layer four today. web on a PiLinuxWindowsmacOSAndroid via Termux SEEN 2026-09-21 LAYER 3 · openwrt.org OpenWrt The Linux that runs the router. Turn off the WAN and the same box is a commons. Every GL.iNet on the shelf ships with it under the hood; LibreMesh and AREDN are built on it. routers SEEN 2026-09-21 LAYER 3 · libremesh.org LibreMesh OpenWrt firmware for a multi-hop community mesh across roofs, batman-adv underneath, one network name for the whole block. routers SEEN 2026-09-21 LAYER 3 · get.kiwix.org Kiwix Offline Wikipedia and more, served from a Pi to every phone on the commons. The full English Wikipedia file was 119 GB when seen; the no-pictures editions fit a small card. Pi serveriOSAndroiddesktop SEEN 2026-09-21 LAYER 3 · syncthing.net Syncthing The shared drive with no server: every device keeps a copy and they sync over the local network. The original Android app was archived in 2024; use the Fork. LinuxAndroid (Syncthing-Fork)iOS (Möbius Sync)desktop SEEN 2026-09-21 LAYER 3 · github.com Meshenger Voice and video calls between phones on the same commons with no server at all, contacts swapped by QR code. Android only. Android SEEN 2026-09-21 LAYER 3 · conduit.rs Conduit A single-binary Matrix chat server that runs on a Pi, so the block can use the Matrix apps it already knows, against a room that lives on the hub. Pi serverLinux SEEN 2026-09-21

THE GROUPS · WHO IS ALREADY ON THE AIR AROUND HERE

SoCal MeshHundreds of Meshtastic nodes across LA, Orange County, the Inland Empire and San Diego. They run the LongTurbo preset on slot 14 (908.750 MHz), region US, so a factory-default node will not see them until you change it. Discord is the door; the live map shows the MQTT-connected nodes.↗RegionMesh — MeshCore Los AngelesThe MeshCore network for the basin. Downtown, the Westside and the Valley are the busy parts; the South Bay is listed as expanding.↗Meshtastic local groupsThe official list, with Laguna, Mission Viejo and the Orange County canyons alongside SoCal Mesh.↗AREDN — the licensed backboneAmateur-radio mesh on roof radios, linking the South Bay to Mt. Wilson. Needs a Technician licence and forbids encryption on the air, so it is a backbone for licensed neighbours, not a commons for phones.↗NYC Mesh wikiThe best-documented community network in the country: how they hang MikroTik and Ubiquiti radios, what fails, what to buy.↗

WATTS PER NODE · WHAT THE MESH COSTS THE BATTERY

LoRa node, nRF52 board (RAK, T-Echo, T1000-E, Seeed Solar Node)measured 4.5–7.5 mA receiving; a 3,000 mAh cell lasts two to four weeks of June gloom with no sun0.04 W
LoRa node, ESP32 board (Heltec, T-Beam)far hungrier than nRF52; fine on a wall wart, wrong for an unattended roof0.5 W
GL.iNet Mango as the commons routerthe spec sheet maximum; 5 V USB2.75 W
Raspberry Pi 5 as the hubidle, measured; about 10 W flat out; a 2 GB board idles at 2.4 W3.3 W
Ubiquiti Loco5AC roof radio, one endthe spec maximum; 24 V passive PoE7 W

A LoRa node draws less in a day than a phone charge. A whole commons hub, router and Pi together, is under a quarter of a kWh a day, which the pocket rung covers on a winter day. The mesh is the cheapest thing on this page to keep on.

METHOD · THE MESH

  1. Agree on one app per layer before the outage, and test it on a sunny afternoon when nothing is wrong. For a block with iPhones that means Bitchat or Berty on layer one, and a LoRa node in every third pocket.
  2. Build the LoRa layer first: it costs the least, reaches the furthest, and needs the least power. Buy nRF52 boards for anything unattended and spend the antenna money; the stock whips are near useless.
  3. To join SoCal Mesh, set LongTurbo, slot 14, region US. A default node hears nothing.
  4. A commons without content is a blinking light. Put Kiwix, a map, the shared drive and a chat room on the Pi before the wire goes down. Plan a 256 GB card if you want the whole Wikipedia.
  5. iPhones stay joined to a Wi-Fi with no internet, but every local app asks for Local Network permission the first time, and the phone may quietly prefer cellular. If a page will not load, Airplane Mode then Wi-Fi back on.
  6. Encryption is fine on the license-free 915 MHz band under FCC Part 15. It is forbidden on amateur bands under Part 97, which is why AREDN is a licensed backbone and not a commons for phones.

WHERE TO BUY · 62 PLACES ON 8 SHELVES · CHECKED SEP 21, 2026

We point. The vendor sells.

We point, the vendor sells. Nothing here is hosted, resold, or marked up. Prices are what a page said on the day we looked, and the day is written next to each one.

Used and surplus panels

Commercial take-offs run 10 to 20 cents a watt. Read the wattage sticker, check the frame and the glass. Snail trails are cosmetic; cracked glass is not.

santansolar.com · NATIONAL SanTan Solar — used panels The largest used-panel reseller in the country, in Gilbert, Arizona. Pallets of 20 to 25 and a one-year warranty on used. Stock seen: SunPower 327 W, JA 310 W, Trina 240 W. prices load in the browser; call or check the page SEEN 2026-09-21 a1solarstore.com · SOCAL A1 SolarStore — Simi Valley pickup New and clearance panels, inverters and batteries with pickup inside 48 hours at the Simi Valley warehouse, the closest big desk to the South Bay. clearance panels $150–250 each on the homepage SEEN 2026-09-21 surplussolar.com · NATIONAL Surplus Solar Products Buys and sells used 335 to 465 W panels from Jinko, Q Cells and LG, plus inverters and racking, from warehouses in New York, California and Texas. pricing by request SEEN 2026-09-21 surplusrecord.com · SOCAL Surplus Record — California solar listings Industrial-surplus classifieds. On the day we looked, Turners Machinery in Santa Paula had REC and Mage panels listed. $65 a panel, minimum six; ET Solar at $220 SEEN 2026-09-21 craigslist.org · SOCAL Craigslist Los Angeles — solar panels Two hundred-plus live listings across the basin: single panels, take-off lots and whole systems from Santa Clarita to Long Beach. single panels from $50, systems $1k–15k SEEN 2026-09-21 facebook.com · SOCAL Facebook Marketplace — solar panels, Los Angeles The other local classifieds. Needs a login to see listings; we confirmed the category page, not the prices. ADDRESS CONFIRMED 2026-09-21 · PAGE BLOCKS ROBOTS ebay.com · ONLINE eBay — used solar panels National search for used and surplus modules. Freight on a pallet matters more than the sticker price here. ADDRESS CONFIRMED 2026-09-21 · PAGE BLOCKS ROBOTS

New panels and kits at wholesale desks

The desks that sell to installers also sell to you. Free freight thresholds and pallet minimums decide the real price.

watts247.com · NATIONAL Watts247 Affordable DIY solar: MPP Solar, Growatt, EG4 and Sol-Ark, rack batteries, and the cheapest new watts we found. Longi 380 W bifacial at 26¢/W; Canadian Solar 695 W pallet $4,000 SEEN 2026-09-21 renvu.com · CALIFORNIA RENVU A California distributor since 2012: Sol-Ark, Enphase, Growatt, racking and balance-of-system parts. Znshine 440 W bifacial $162.86, about 37¢/W SEEN 2026-09-21 signaturesolar.com · NATIONAL Signature Solar Home of the EG4 brand: panels, inverters, batteries and kits from Texas. Free shipping over $4,000. EG4 WallMount 280 Ah $2,700 on the banner SEEN 2026-09-21 solar-electric.com · NATIONAL Northern Arizona Wind & Sun Selling off-grid gear since 1979, strong on MidNite, Victron and Sol-Ark, with people who answer the phone. REC 460 W $251.47; Sol-Ark 15K $5,669.33 SEEN 2026-09-21 currentconnected.com · NATIONAL Current Connected Victron, EG4, SOK, Pytes and Sol-Ark, custom cables, and long product pages that explain the listings. Pytes V5 $1,450 SEEN 2026-09-21 shopsolarkits.com · NATIONAL Shop Solar Kits Bundled kits and portable-station packages when you would rather not spec every part. 100 W panel $89.99; 400 W foldable $599; EcoFlow Delta Pro kits from $1,899 SEEN 2026-09-21 altestore.com · NATIONAL altE Store Off-grid and DIY kits since 1999, quote-driven for anything past a single panel. SEEN 2026-09-21

LiFePO4 batteries

Look for UL 1973 on a rack battery and UL 9540 on a battery-plus-inverter system if it will ever touch a permit. Budget drop-ins are fine on the small rungs.

signaturesolar.com · NATIONAL EG4 LifePower4 V2 — 48 V 100 Ah The 5.12 kWh server-rack battery the house rung is built on. Built-in breaker, ten-year warranty. The page states UL 1973 recognized, UL 9540A tested, UL 9540 listed. $1,470.99, about $287/kWh SEEN 2026-09-21 us.sokbattery.com · SOCAL SOK SK48V100N — 48 V 100 Ah A user-serviceable 3U rack battery with a heater and a seven-year warranty, shipped from a warehouse in Chino, California. No UL statement on the page. $1,199 on sale, $1,499 regular, about $234/kWh SEEN 2026-09-21 signaturesolar.com · NATIONAL EG4 WallMount — 280 and 314 Ah The 14 kWh indoor wall battery for a house that wants one box instead of a rack. 280 Ah $2,700; 314 Ah indoor $3,399.99; all-weather $3,749.99 SEEN 2026-09-21 litime.com · NATIONAL LiTime Budget 12, 24 and 48 V drop-ins, formerly Ampere Time. The 48 V ComFlex talks to Victron gear. 12 V 100 Ah $338–366; 48 V 100 Ah $949.99 SEEN 2026-09-21 redodopower.com · NATIONAL Redodo Budget 12 V 100 Ah drop-ins for the pocket and shed rungs. prices load in the browser SEEN 2026-09-21 battlebornbatteries.com · NATIONAL Battle Born The premium 12 V drop-in, assembled in Reno with a ten-year warranty. You pay for the support line. 12 V 100 Ah $799 on sale, $949 regular SEEN 2026-09-21 docanpower.com · NATIONAL Docan Power — prismatic cells EVE and CATL prismatic LiFePO4 cells from Texas stock for people building their own packs. Sixteen-cell minimum. EVE 280 Ah $94, 304 Ah $103 a cell, about 11¢/Wh SEEN 2026-09-21 batteryhookup.com · NATIONAL Battery Hookup Salvage and new cells, modules and BMS boards. Where the cheapest watt-hours live if you can solder. cells from $2.16; modules $29–46; BMS $11–110 SEEN 2026-09-21 18650batterystore.com · NATIONAL 18650 Battery Store Samsung and Molicel cylindrical cells and EVE MB31 prismatics from Georgia. EVE MB31 four-pack $299 on sale SEEN 2026-09-21

Controllers and inverters

One all-in-one at 48 V replaces three boxes. Victron costs more and lasts; EG4 and MPP are the value line. Anything hardwired wants UL 1741 on the label.

signaturesolar.com · NATIONAL EG4 6000XP The 6 kW split-phase all-in-one the house rung assumes: 8 kW of PV in, 48 V battery, UL 1741 certificate on the page. $1,499.99 on sale, $1,629.99 list SEEN 2026-09-21 currentconnected.com · NATIONAL EG4 3000EHV-48 The 3 kW 120 V all-in-one for the shed rung: 5 kW of PV, 500 V MPPT, parallels to twelve later. $699.99, out of stock when seen SEEN 2026-09-21 watts247.com · NATIONAL MPP Solar and Humless — via Watts247 The value line of all-in-ones. The Humless LVX6048WP is a 6 kW outdoor split-phase unit with UL 1741. LVX6048WP $1,199 on sale; LV6548 plus 15 kWh bundle $3,499 SEEN 2026-09-21 baymarinesupply.com · SOCAL Victron — Bay Marine Supply, San Diego A Victron True Blue distributor two hours south, with 199 Victron parts on the shelf and a counter. SmartShunt 300 A $85.85; MultiPlus 12/500 $308.55 SEEN 2026-09-21 bluemarine.com · NATIONAL Victron — Blue Marine The full Victron range with free shipping over $49. SmartSolar MPPT 100/30 $135.15; MultiPlus-II 12 V from $849.95 SEEN 2026-09-21 renogy.com · NATIONAL Renogy The 12 V starter brand: Rover MPPT controllers, small panels, sockets and cables for the pocket rung. Rover Li MPPT from $87.99; 100 W panel from $109.99 SEEN 2026-09-21 victronenergy.com · INTERNATIONAL Victron — where to buy Victron's own dealer map, for finding the counter nearest you. SEEN 2026-09-21

Wiring and the parts that stop fires

Genuine MC4, Anderson for anything you unplug, a Class T fuse at the battery, DC-rated breakers, real copper. This shelf is cheap; skipping it is not.

signaturesolar.com · NATIONAL Stäubli MC4 pair The genuine connector, 12 to 10 AWG, 25-year warranty. Counterfeit MC4s are where roof fires start. $4.60 a pair SEEN 2026-09-21 bendbattery.com · NATIONAL Anderson SB50 and SB175 — Bend Battery The plug for anything that comes off the bus: battery leads, portable loads, the sneakernet. SB50 $12.95; SB175 $21.99 SEEN 2026-09-21 powerwerx.com · SOCAL Powerwerx — Anderson SB connectors The canonical Anderson source, in Brea, Orange County. The site blocks robots; we confirmed the page, not the price. ADDRESS CONFIRMED 2026-09-21 · PAGE BLOCKS ROBOTS baymarinesupply.com · SOCAL Blue Sea 5502 Class T fuse block The fuse block for a 48 V lithium bank, 225 to 400 A, 160 V DC. Fuse sold separately. San Diego counter. $46.30 SEEN 2026-09-21 solar-electric.com · NATIONAL MidNite Solar MNEPV DC breakers — via NAZ 150 V DC DIN-rail breakers from 1 to 63 A between the panels and the controller. from $25.19 SEEN 2026-09-21 windynation.com · SOCAL WindyNation welding cable US-made pure-copper battery cable from 8 to 4/0 AWG, with back-door pickup at the Ventura warehouse. 4 AWG from $22.97; 2 AWG from $34.16 SEEN 2026-09-21 temcoindustrial.com · NATIONAL TEMCo 2 AWG welding cable, 50 ft US-made 205 A EPDM cable with free shipping, for the runs between battery, fuse and inverter. $127.68 direct SEEN 2026-09-21 shop.poetexas.com · NATIONAL PoE Texas 8-port 48 V injector Puts eight radios or cameras on a 48 V bank with one box. The DC-bus distribution rung starts here. $47.99 SEEN 2026-09-21 ultrapoe.com · NATIONAL UltraPoE PoE-N912-2SL48 12 to 48 V DC in, 802.3at PoE+ out, DIN rail, rated to 80 °C, built for standalone solar cabinets. $159 SEEN 2026-09-21

LoRa mesh radios

Buy nRF52 for anything unattended, ESP32 for the desk. Rokland in Florida is the US counter; the makers ship from Shenzhen and sell out.

store.rokland.com · NATIONAL RAK WisBlock Meshtastic starter kit — US915 The nRF52840 node that runs for weeks on a cell, pre-flashed, solar input on the base board. The relay we would put on a roof. $34.97 SEEN 2026-09-21 seeedstudio.com · INTERNATIONAL Seeed SenseCAP T1000-E card A credit-card LoRa node with GPS and a week of battery, IP65. The one you hand to a neighbour who will never open a settings screen. $39.90 SEEN 2026-09-21 seeedstudio.com · INTERNATIONAL Seeed SenseCAP Solar Node P1-Pro The turnkey rooftop repeater: 5 W panel, four 18650 cells, GPS, nRF52 and an RP-SMA socket for a real antenna. Eight to nine km in the open, says the maker. $100.99 SEEN 2026-09-21 store.rokland.com · NATIONAL Heltec WiFi LoRa 32 V3 — Rokland The entry ESP32 board with a screen, the one every tutorial uses. Fine on a desk, hungry on a roof. $29.97 SEEN 2026-09-21 store.rokland.com · NATIONAL Heltec WiFi LoRa 32 V4 — Rokland The V3 with a stronger radio, a solar connector on the board and deep sleep under 20 µA. Needs recent firmware. $26.97 SEEN 2026-09-21 store.rokland.com · NATIONAL LILYGO T-Beam and T-Echo series — Rokland GPS boards with an 18650 holder, the e-paper T-Echo, and the keyboard T-Deck, in US stock while the maker’s own store was sold out. T-Beam 1W $62.97; T-Echo $64.97; T-Echo Lite $44.97 SEEN 2026-09-21 lilygo.cc · INTERNATIONAL LILYGO T-Echo — maker’s store The nRF52840 e-paper node with GNSS, direct from Shenzhen. Sold out when seen. $48.49 SEEN 2026-09-21 store.rokland.com · NATIONAL Rokland 5.8 dBi outdoor 915 MHz antenna kit The fiberglass omni and cable that turn a $35 node into the relay the block can hear. $49.97 with 6 to 15 ft of cable SEEN 2026-09-21 heltec.org · INTERNATIONAL Heltec — maker’s store The V3 direct, cheaper and slower, with a US warehouse option on some listings. $17.90–19.90 SEEN 2026-09-21 adafruit.com · NATIONAL Adafruit LoRa boards Feather RFM95 boards and the Pi LoRa bonnet for RNode and experiments. Not first-class Meshtastic targets, and no Heltec or RAK stock. FeatherWing RFM95W $19.95; Pi LoRa Bonnet $32.50 SEEN 2026-09-21

The commons: routers, roof radios, the hub

A travel router with the WAN unplugged, a Pi beside it, and a pair of roof radios per hop. All of it runs on 5 V or passive PoE from the 48 V bus.

gl-inet.com · NATIONAL GL.iNet Mango GL-MT300N-V2 A 40-gram OpenWrt router that draws under 3 W. The cheapest commons that exists. $29.99 SEEN 2026-09-21 gl-inet.com · NATIONAL GL.iNet Opal GL-SFT1200 Dual-band AC1200 with three gigabit ports for a house-sized commons, USB-C powered. $39.99 SEEN 2026-09-21 gl-inet.com · NATIONAL GL.iNet Beryl AX GL-MT3000 Wi-Fi 6 with a 2.5 Gb port, measured under 3.5 W in use. The commons router for a hub that serves video. $98.99 SEEN 2026-09-21 store.ui.com · NATIONAL Ubiquiti NanoStation 5AC Loco The 5 GHz roof-to-roof radio, 13 dBi, 24 V passive PoE, 7 W. Two of these are one hop of a street. $49 plus a $3 surcharge SEEN 2026-09-21 mikrotik.com · INTERNATIONAL MikroTik SXTsq 5 ac The other roof radio, 16 dBi, RouterOS, 7 W. What NYC Mesh hangs. $65 suggested SEEN 2026-09-21 raspberrypi.com · INTERNATIONAL Raspberry Pi 5 — official page The hub. Idles at 2.4 to 3.3 W, ten flat out; wants the 27 W supply. 16 GB $305 on the official page SEEN 2026-09-21 pishop.us · NATIONAL Raspberry Pi 5 8 GB — PiShop The US reseller that had the 8 GB board in stock and cheapest when seen. $175 SEEN 2026-09-21 adafruit.com · NATIONAL Raspberry Pi 5 — Adafruit Adafruit’s listing, with cases, supplies and the cards to go with it. 4 GB $130; 8 GB $200; 16 GB $350 SEEN 2026-09-21 download.kiwix.org · ONLINE Kiwix Wikipedia files The ZIM files the hub serves. Full English with pictures was 119 GB in the August 2026 edition; the no-picture editions are a tenth of that. free SEEN 2026-09-21

RULES & MONEY · EL SEGUNDO · CALIFORNIA · FEDERAL · WHAT WE COULD VERIFY, AND WHEN

The rules changed in 2025 and 2026. Here is where they stood.

EL SEGUNDO · ADDRESS CONFIRMED 2026-09-21 · PAGE BLOCKS ROBOTS

El Segundo automated residential solar permitting (SolarAPP+)

The city is in the SolarAPP+ pilot: instant permits for roof-mounted PV and storage on single-family homes, applied for and paid online by a licensed contractor. The city site blocks robots, so we confirmed the address through the search index. Open it in a browser.

elsegundo.gov ↗

EL SEGUNDO · ADDRESS CONFIRMED 2026-09-21 · PAGE BLOCKS ROBOTS

El Segundo Building and Safety Division

The counter for anything SolarAPP+ does not cover: ground mounts, subpanels, transfer switches, a DC bus through a wall. Ask before you drill.

elsegundo.gov ↗

UTILITY · SEEN 2026-09-21

SCE Solar Billing Plan (what people call NEM 3.0)

Export credits run roughly 3 to 23 cents a kWh depending on hour and season, highest 4 to 9 pm in June through September, plus a small residential adder. Storage is what makes exports worth anything. The interconnection request lives on this page.

sce.com ↗

UTILITY · SEEN 2026-09-21

SCE net energy metering (closed to new applicants)

NEM 2.0 closed on April 15, 2023. New systems go to the Solar Billing Plan. The application fee for systems under 1 MW was $94 when seen.

sce.com ↗

CALIFORNIA · SEEN 2026-09-21

CPUC customer generation and net billing

The regulator’s own page on the Net Billing Tariff in force since April 15, 2023. The CPUC never calls it NEM 3.0; the utilities and everyone else do.

cpuc.ca.gov ↗

CALIFORNIA · SEEN 2026-09-21

California Solar Consumer Protection Guide

Version 4, 2025, in nine languages. Any solar provider in California must hand it to you at first contact. Read it before you sign anything, including a lease.

cpuc.ca.gov ↗

CALIFORNIA · SEEN 2026-09-21

Self-Generation Incentive Program (SGIP)

The Residential Solar and Storage Equity budget opened June 2, 2025 with $1,100 per kWh of storage and $3,100 per kW of solar for qualifying low-income households, $280 million in all. Installer-applied, not DIY.

cpuc.ca.gov ↗

CALIFORNIA · SEEN 2026-09-21

SGIP applicant portal

The 2026 SGIP handbook, the step tracker and the waitlists. Southern California Edison is the program administrator for El Segundo.

selfgenca.com ↗

CALIFORNIA · SEEN 2026-09-21

GoGreen Home energy financing

State-backed loans for solar, batteries and efficiency with no lien on the house, open to SCE and SoCalGas customers, owners and renters with permission. It has a do-it-yourself section, which is rare.

gogreenfinancing.com ↗

CALIFORNIA · SEEN 2026-09-21

SB 868, the Plug and Play Solar Act — on the Governor’s desk

Passed the Assembly 73 to 0 on August 25 and the Senate 36 to 4 on August 26, enrolled to the Governor August 31, 2026. Deadline to sign or veto is September 30. Not signed when seen. If signed: up to 1,200 W AC per dwelling plugged into a standard receptacle, no interconnection application or fee, certified anti-backfeed equipment, effective January 1, 2027, sunset January 1, 2030. Until then plug-in solar is a grey area here.

leginfo.legislature.ca.gov ↗

CALIFORNIA · SEEN 2026-09-21

Plug-in solar explainer — Solar Rights Alliance

The plain-language page on what SB 868 does and does not allow, kept current by the group that carried it.

solarrights.org ↗

ELSEWHERE · SEEN 2026-09-21

Utah HB 340 — the first US plug-in solar law

Signed March 25, 2025, in force May 7, 2025. Up to 1,200 W AC at the inverter into a standard 120 V outlet, anti-islanding required, no permit or utility approval, no net metering. Passed 72 to 0 and 27 to 0. It is the template California’s bill follows.

pluginsolarutah.com ↗

FEDERAL · SEEN 2026-09-21

IRS: the 25D residential clean energy credit ended

No credit for expenditures after December 31, 2025, and an expenditure counts when the installation is completed, not when you paid. Credits earned before 2026 can still be carried forward. Price the ladder without it.

irs.gov ↗

FEDERAL · SEEN 2026-09-21

47 CFR 15.247 — the license-free 902–928 MHz band

Meshtastic, MeshCore and RNode radios operate here under Part 15: no licence, up to 1 W conducted for digital modulation, encryption allowed. Meshtastic caps North America at +30 dBm ERP. The eCFR itself blocks robots; this is Cornell’s mirror.

law.cornell.edu ↗

FEDERAL · SEEN 2026-09-21

47 CFR 97.113 — no obscured messages on amateur bands

Amateur radio forbids messages encoded to obscure their meaning, which is why an AREDN mesh cannot carry encrypted chat or HTTPS the way a Part 15 mesh can. Use the ham backbone for what it is good at and keep the phones on 915 MHz and Wi-Fi.

law.cornell.edu ↗

FEDERAL · SEEN 2026-09-21

ARRL — getting a Technician licence

Thirty-five questions and a $35 FCC application fee, good for ten years. The door to AREDN and to the Mt. Wilson links the South Bay hams already run.

arrl.org ↗

SAFETY · THE SHORT LIST

  1. Fuse every battery lead at the battery. A Class T fuse on 48 V packs; the short-circuit current of LiFePO4 will weld an ordinary fuse shut.
  2. DC-rated breakers or a disconnect between panels and controller. Solar DC arcs do not self-extinguish.
  3. A BMS with low-temperature charge cutoff. Lithium plates below freezing; El Segundo rarely gets there, garages sometimes do.
  4. A ground rod and bonded frames for any fixed array. Rapid shutdown and labels once it touches the house.
  5. Never backfeed a house panel without a transfer switch. Suicide cords are named accurately.
  6. Nothing on this page is electrical advice. Hardwired AC is a licensed electrician's job in California, and the permit protects you and the next owner.

LEARN · THE PEOPLE WHO TAUGHT US

DIY Solar Power Forum1.9 million posts from 173,000 people who have made every mistake first. The marketplace subforum is a real source of used gear.↗Will Prowse’s approved shopThe list behind the most-watched DIY solar channel, split into certified permit-ready gear and budget gear. His affiliate links, not ours.↗Off-Grid GarageAndy in Australia tears down LiFePO4 cells and BMS boards on camera. Watch before you buy a battery you cannot open.↗PVWattsThe free production model behind every number on this page. The lab was renamed the National Laboratory of the Rockies; the old nrel.gov address no longer resolves.↗Global Solar AtlasWorld Bank and Solargis maps of solar yield anywhere on earth. Be careful which pixel you click; a Mojave point is often quoted for Los Angeles.↗EnergySageInstaller quotes and equipment comparisons, for the day the ladder stops being a hobby and needs a contractor.↗Solar Power World on the secondhand marketWhy used modules sell 50 to 75 percent below new, and who trades them at scale.↗Meshtastic — solar-powered nodesHow to measure what a node actually draws before you size its panel. Some nodes sit at 25 mW.↗Jeff Geerling on Pi 5 powerThe measured idle and load numbers behind the hub row above.↗

METHOD · HOW TO READ THIS

  1. Every price is what a vendor's own page said on the day written next to it. Prices move; the day is the fact.
  2. Every link goes to the seller or the agency, never a middle page. We point, the vendor sells.
  3. The yields are PVWatts v8 numbers for the weather station 1.7 km from LAX with the calculator's default losses, not a sunny-day brochure. The run is in the JSON twin.
  4. The rungs are budgets, not kits. Parts on each rung name a shelf, and the shelf names the vendors.
  5. Rules are dated. California and the federal credit both changed in 2025 and 2026; the rules shelf says what we could verify and when.
  6. Nothing here is inside information, sponsorship, or an affiliate link.

the whole guide as JSON · block 0602 · pool together · el segundo · compiled 2026-09-21 · CC0