• BigBattery ETHOS 2-battery kit with EG4 18kPV hybrid inverter
  • BigBattery ETHOS stackable LiFePO4 battery module
  • EG4 18kPV all-in-one hybrid solar inverter, open angle view
  • EG4 18kPV hybrid solar inverter, side angle view
  • BigBattery ETHOS 3-battery 15.36 kWh configuration
  • BigBattery ETHOS 4-battery 20.48 kWh configuration
  • BigBattery ETHOS 6-battery 30.72 kWh configuration
BigBattery ETHOS 2-battery kit with EG4 18kPV hybrid inverter
BigBattery ETHOS stackable LiFePO4 battery module
EG4 18kPV all-in-one hybrid solar inverter, open angle view
EG4 18kPV hybrid solar inverter, side angle view
BigBattery ETHOS 3-battery 15.36 kWh configuration
BigBattery ETHOS 4-battery 20.48 kWh configuration
BigBattery ETHOS 6-battery 30.72 kWh configuration

BigBattery

BigBattery ETHOS + EG4 18kPV Hybrid Inverter Kit | 10.24–30.72 kWh | Whole-Home Solar ESS

SKU K0954
$7,755.00
$7,755.00
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Estimated Delivery - 5-9 Business Days from Order Date

Free Shipping on All Orders to the Contiguous USA

30 Day Return Policy with 25% restocking fee applies to change-of-mind returns. See full policy

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OffGrid Horizon Authorized DealerOffGrid Horizon Family Owned and Operated

Authorized BigBattery dealer — see our dealer list. Sold and supported by OffGrid Horizon (JBrophy ECommerce LLC), Newark, Delaware.

Estimated Shipping Time

Effective Date: August 28, 2026

1. Introduction

At OffGrid Horizon ("we," "us," or "our"), we aim to provide a seamless and transparent shipping experience for our customers. This Shipping Policy outlines the terms and conditions related to the delivery of products purchased from our website, offgridhorizon.com. OffGrid Horizon is operated by JBrophy ECommerce LLC, a Delaware limited liability company.

2. Shipping Destinations

  • Countries We Ship To: Contiguous United States.
  • We do not ship internationally at this time.

3. Shipping Costs

Domestic Shipping: Free standard shipping on all orders. There are no hidden fees or additional shipping charges at checkout.

4. Order Processing Time

  • Handling Time: Orders are processed with a handling time of 1-2 business days. Orders are fulfilled Monday through Friday (excluding holidays).
  • Weekend and Holiday Orders: Orders placed on weekends or public holidays will be processed on the next business day.
  • Backorders: Pre-order and backorder items display their expected lead time on the product page, and that date takes precedence over the general estimates below.

5. Estimated Delivery Time

Domestic Shipping:

  • Transit Time: 4-7 business days for all destinations. Orders are shipped Monday through Friday.
  • Total Estimated Delivery Time: 5-9 business days from the date the order is placed.

Note: Delivery times are estimates and may vary due to factors beyond our control, such as weather conditions or carrier issues.

6. Shipping Methods and Carriers

  • Reliable Carriers: We partner with reputable carriers to ensure your package arrives safely.
  • Large or Freight Items: Large items ship by LTL freight carrier. The carrier will call to schedule a delivery appointment.
  • Shipment Tracking: All orders include tracking information, which will be provided via email once your order has shipped.
  • Insurance: Shipments are insured against loss or damage. If you encounter any issues, please contact us promptly.

7. Order Tracking

After your order has been shipped, you will receive an email containing: Tracking Number, Carrier Name, and Tracking instructions.

You can track your package directly on the carrier's website using the tracking number provided in your shipping confirmation email, or through our order tracking page.

If you have questions or need assistance with tracking, please contact our Customer Service team at sales@offgridhorizon.com or (302) 496-3554.

8. Delivery Issues

8.1 Delayed or Lost Packages. Delayed Delivery: If your package is delayed beyond the estimated total delivery time, please contact us at sales@offgridhorizon.com or (302) 496-3554. Lost Packages: If your tracking information indicates that your package was delivered but you have not received it: verify the shipping address provided; check with neighbors or building management; contact us for further assistance.

8.2 Damaged Packages. If your package arrives damaged: take photos of the damaged packaging and items; contact us within 30 days of delivery at sales@offgridhorizon.com. Damaged items are eligible for a full refund or replacement, with return shipping covered by us. We will work with you to arrange a replacement or refund as appropriate.

9. Missing Items

If any items are missing from your order: contact us within 30 days of receiving your package; provide your order number and details of the missing item(s). We will investigate and resolve the issue promptly by sending the missing item(s) or offering a refund.

10. Return and Refund Policy Summary

  • Returns are accepted within 30 days of receiving your order, for both defective and non-defective products.
  • Non-defective returns must be unused and in original, unopened packaging with all labels, accessories, and manuals.
  • Customer pays for return shipping on change-of-mind returns; OffGrid Horizon covers return shipping for defective, damaged, or incorrect items.
  • A 25% restocking fee applies to change-of-mind returns. No restocking fee applies to defective or damaged goods.
  • Refund processing time is within 14 days after we receive and inspect the returned item.

For complete details, please refer to our Return and Refund Policy.

11. Incorrect Address

Please ensure that all shipping information is correct. We are not responsible for orders shipped to incorrect addresses provided by the customer. If a package is returned to us due to an incorrect address: we will contact you to arrange reshipment; additional shipping charges may apply.

12. Contact Information

OffGrid Horizon (JBrophy ECommerce LLC)

Email: sales@offgridhorizon.com

Phone: (302) 496-3554

Address: 262 Chapman Rd, Ste 240, Newark, DE 19702, United States

Hours: Monday to Friday, 9 AM to 4 PM ET

What is your Return Policy?

Effective Date: August 28, 2026

1. Overview (Quick Reference)

  • Return Window: 30 days from delivery
  • Product Condition Accepted: New (unused, original unopened packaging, labels and manuals included) for change-of-mind returns; any condition for defective or damaged items
  • Return Method: By mail (small parcel) or arranged freight pickup for large items
  • Return Shipping Cost: Customer pays for change-of-mind returns; OffGrid Horizon pays for defective, damaged, or incorrect items
  • Restocking Fee: 25% for change-of-mind returns; 0% for defective, damaged, or incorrect items
  • Refund Processing Time: Within 14 days after we receive and inspect the returned item
  • Refund Method: Original payment method
  • Exchanges: Accepted for defective, damaged, or incorrect items

2. Scope and Intent

This Return and Refund Policy applies to all purchases made through the OffGrid Horizon website located at offgridhorizon.com ("Website") and shipped to customers within the contiguous United States. OffGrid Horizon is operated by JBrophy ECommerce LLC.

3. Contact Information

For questions about returns and refunds, please contact our Customer Service team:

Email: sales@offgridhorizon.com

Phone: (302) 496-3554

Address: 262 Chapman Rd, Ste 240, Newark, DE 19702, United States

Hours: Monday to Friday, 9 AM to 4 PM ET

4. Return Eligibility

Customers have the right to return products within 30 days of receipt, subject to the conditions outlined below. We accept returns for both defective and non-defective products.

4.1 Conditions for Return

  • For Non-Defective Returns (Change of Mind): The product must be unused and in its original, unopened packaging, with all labels, accessories, manuals, and any included gifts.
  • For Defective or Damaged Returns: Items are accepted regardless of condition. Please provide photos or videos as documentation of the defect or damage.
  • Proof of Purchase: Your order number serves as proof of purchase.

5. Return Process

5.1 Initiating a Return. Contact Customer Service: Email us at sales@offgridhorizon.com or call (302) 496-3554 within 30 days of receiving your order. Provide your order number and a detailed reason for the return. Return Authorization: We reply within one business day with a Return Merchandise Authorization (RMA) number and the return address for your item — depending on the brand, returns go to our U.S. partner warehouse or to the manufacturer's U.S. service center. Please do not ship returns to our registered office address and do not ship without an RMA. Please note that change-of-mind returns are subject to a 25% restocking fee, which will be deducted from your refund.

5.2 Preparing Your Return. Package the Item Safely: Securely pack the item in its original packaging with all accessories, manuals, and free gifts included. Include Documentation: Include the return authorization form and any necessary supporting documents or images. Return Label: For change-of-mind returns, you are responsible for arranging and paying for trackable return shipping (freight items must ship by LTL carrier; we can quote a rate). For defective, damaged, or incorrect items, OffGrid Horizon will provide a prepaid return label or arrange freight pickup for large items.

5.3 Shipping the Return. Method: Return using a trackable shipping method. Risk of loss remains with you until the return is received, so please insure high-value items. Return Window: Ship the item promptly after receiving the return authorization.

6. Return Shipping Costs and Fees

  • Return Shipping Costs (Change of Mind): The customer is responsible for return shipping costs.
  • Return Shipping Costs (Defective, Damaged, or Incorrect Items): OffGrid Horizon covers return shipping costs.
  • Restocking Fees: A 25% restocking fee applies to change-of-mind returns. No restocking fee applies to defective, damaged, or incorrect items.

7. Specific Return and Refund Conditions

7.1 Returns Due to Change of Mind (Non-Defective Products). Eligibility: Items must be unused and in original, unopened packaging. Return request must be made within 30 days of receipt. Refund: A refund will be issued to the original payment method, minus a 25% restocking fee. Return shipping is the customer's responsibility.

7.2 Defective or Damaged Goods. Notification: Report the problem within 30 days of delivery. Documentation: Provide photos or videos of the defect or damage. Resolution: We send a prepaid return label (or arrange freight pickup for large items). Once received and inspected, we issue a full refund, including any original shipping costs, or a free replacement. No restocking fee applies.

7.3 Incorrect Product Received. Notification: Inform us immediately upon receipt. Resolution: We will arrange for the incorrect item to be returned at our expense and ensure you receive the correct product at no additional cost.

7.4 Product Never Arrived. Notification: Contact us if your product does not arrive within the estimated delivery time stated in our Shipping Policy. Resolution: We will initiate an investigation with the carrier. If the product is confirmed lost, we will offer a full refund or send a replacement product.

7.5 Order Cancellation. Before Shipment: You can cancel your order for a full refund by contacting us right away with your order number — cancellations are not self-serve. In-stock orders begin processing within 1-2 business days, so we cannot guarantee cancellation once an order has been released to the carrier. Pre-order and backorder items may be cancelled for a full refund at any time before they ship. After Shipment: If the order has already been shipped, please follow the return process once received.

8. Refunds

8.1 Refund Conditions. Approval: Refunds are issued after we receive and inspect the returned item. Notification: We will notify you via email regarding the approval or rejection of your refund. Condition: Items must meet the return eligibility criteria outlined in Section 4.

8.2 Refund Processing. Method: Refunds will be processed to the original payment method used at the time of purchase. Processing Time: After receiving and inspecting the returned item, the refund is issued within 14 days. It may take additional time for the refund to appear in your account, depending on your bank or credit card issuer.

8.3 Partial Refunds. Partial refunds may be granted in certain situations: Condition Issues: Items returned incomplete or not in original condition for reasons other than our error. Late Returns: Items returned more than 30 days after delivery.

9. Exchanges

We accept exchanges. Defective, damaged, or incorrect items are exchanged free of charge. Change-of-mind exchanges are handled as a return under the terms above, plus a new order. To request an exchange, contact us at sales@offgridhorizon.com.

10. Non-Returnable Items

The following items are not eligible for return or refund: Custom or personalized items, and items made to your specifications; Gift cards; Opened food storage products. Legacy food storage products may be returned within 30 days if the outer packaging is unopened, under the change-of-mind terms above.

11. Timelines

  • Return Window: Returns must be reported within 30 days of receiving the product.
  • Damage/Defect Reporting: Within 30 days of delivery.
  • Return Authorization Response Time: Within 1 business day.
  • Refund Processing Time: Within 14 days after receiving and inspecting the returned item.

12. Legal Rights

This Return and Refund Policy does not affect any statutory rights you may have under applicable law.

13. Questions and Support

OffGrid Horizon (JBrophy ECommerce LLC)

Phone: (302) 496-3554

Email: sales@offgridhorizon.com

Business Hours: Monday to Friday, 9 AM to 4 PM ET

Address: 262 Chapman Rd, Ste 240, Newark, DE 19702, United States

Note: By making a purchase on our Website, you agree to this Return and Refund Policy.

BigBattery ETHOS 2-battery kit with EG4 18kPV hybrid inverter BigBattery ETHOS stackable LiFePO4 battery module EG4 18kPV all-in-one hybrid solar inverter, open angle view EG4 18kPV hybrid solar inverter, side angle view BigBattery ETHOS 3-battery 15.36 kWh configuration BigBattery ETHOS 4-battery 20.48 kWh configuration BigBattery ETHOS 6-battery 30.72 kWh configuration
BigBattery ETHOS 2-battery kit with EG4 18kPV hybrid inverter BigBattery ETHOS stackable LiFePO4 battery module EG4 18kPV all-in-one hybrid solar inverter, open angle view EG4 18kPV hybrid solar inverter, side angle view BigBattery ETHOS 3-battery 15.36 kWh configuration BigBattery ETHOS 4-battery 20.48 kWh configuration BigBattery ETHOS 6-battery 30.72 kWh configuration

BigBattery

BigBattery ETHOS + EG4 18kPV Hybrid Inverter Kit | 10.24–30.72 kWh | Whole-Home Solar ESS

SKU K0954
$7,755.00
BigBattery ETHOS 2-battery kit with EG4 18kPV hybrid inverter

Product Description

This kit pairs BigBattery's stackable ETHOS 48V LiFePO4 battery platform with the EG4 18kPV all-in-one hybrid inverter. Per EG4, the 18kPV accepts 18 kW of PV input across three MPPTs and delivers 12 kW of continuous split-phase 120/240V output, with grid-tied, grid-assist, and off-grid modes in one wall-mounted unit. ETHOS storage in this listing is configurable from 10.24 to 30.72 kWh, and per BigBattery the two operate with closed-loop communication for coordinated charging and accurate state-of-charge reporting.

Who This System Is For

Homeowners who want one inverter to manage solar, battery, grid, and generator power — whether the goal is solar self-consumption, time-of-use offset, backup for essential circuits, or a path toward broader home coverage. Because ETHOS stacks in 5.12 kWh steps, this kit suits buyers who want to start with the storage they need now and grow later without replacing equipment.

Key Features

  • 18 kW of PV input across three MPPTs, per EG4 — headroom for large rooftop or ground-mount arrays
  • 12 kW continuous split-phase output (120/240V or 120/208V), per EG4
  • Grid-tied, grid-assist, and off-grid modes, including selling excess power back to the grid where your utility approves interconnection, per EG4
  • Certified battery platform: ETHOS carries UL9540, UL9540A, UL1973, and UN38.3, per BigBattery; the 18kPV is UL1741 SB listed with CEC and CSIP compliance, per EG4
  • Closed-loop communication between ETHOS and the inverter, per BigBattery
  • Expandable both ways: stack additional ETHOS modules (up to 16 parallel connections per control box, per BigBattery) or parallel up to 10 inverters, per EG4
  • Small-footprint tower: ETHOS modules stack vertically instead of spreading across a wall

Why BigBattery

BigBattery is a US-based energy storage company that has been building lithium battery systems since 2011 and, per BigBattery, is trusted by more than 50,000 Americans. BigBattery states its products are designed and engineered in Texas, includes free lifetime tech support with every product, and backs its batteries with a 12-Year Limited Warranty — described by BigBattery as "the longest warranty in the battery industry." OffGrid Horizon is a family-owned authorized BigBattery partner.

What's In the Kit

  • 1 × EG4 18kPV all-in-one hybrid solar inverter
  • BigBattery ETHOS 48V 5.12 kWh LiFePO4 modules — capacity for this listing is configurable from 10.24 to 30.72 kWh (2–6 modules)

Please call (302) 496-3554 to confirm the module count and configuration that ships at the listed price. BigBattery lists ETHOS inverter connectors and battery-to-battery connectors as separate accessories, so also confirm cabling with your order. Solar panels, racking, and array wiring are sold separately. For whole-home load management, AC coupling, and generator integration, ask about adding the EG4 GridBOSS MID.

Specifications

Battery BigBattery ETHOS, stackable LiFePO4
Module capacity 5.12 kWh / 100Ah per module, 51.2V nominal
Capacity (this listing) Configurable 10.24–30.72 kWh — call to confirm configuration
Max continuous discharge 200A (2-module stack) / 250A (3+ modules), per BigBattery
Battery communications CAN bus / RS485; closed-loop with EG4, per BigBattery
Battery certifications UL9540, UL9540A, UL1973, UN38.3, per BigBattery
Cycle life 3,500–5,000 cycles (80% DoD, 0.5C), per BigBattery's spec sheet
Battery warranty BigBattery 12-Year Limited Warranty
Inverter EG4 18kPV all-in-one hybrid (per EG4)
PV input 18 kW max, 600V DC input, 3 MPPTs
AC output 12 kW continuous, split-phase 120/240V or 120/208V
Operating modes Grid-tied (with export), grid-assist, off-grid, battery backup
Parallel capability Up to 10 units
Inverter certifications UL1741 SB, NEMA 4X, CEC, CSIP
Inverter warranty 10-year, per EG4 (registration required — see below)

Grid-Tied, Off-Grid, or Backup?

All three. Per EG4, the 18kPV supports grid-tied operation with export (subject to your utility's interconnection approval), grid-assist and self-consumption modes that favor solar and battery over grid power, true off-grid operation, and battery backup during outages. Whole-home backup is possible with adequate inverter capacity and load management, but coverage is load-dependent — a 12 kW inverter carries most household circuits, and heavy simultaneous 240V loads should be reviewed during system design. The system also runs without solar panels as grid-charged battery backup.

Installation

All AC and DC wiring — panel interconnection, grounding, bonding, and overcurrent protection — must be performed by a licensed electrician in accordance with the National Electrical Code (NEC) and local amendments. Residential energy storage installations typically require a permit and inspection, and grid-tied operation requires an approved interconnection agreement with your utility before the system may export power. Your installer should verify conductor sizing, disconnects, and clearances against current NEC requirements for energy storage systems.

Warranty & Support

Battery — BigBattery 12-Year Limited Warranty. Per BigBattery: "If any covered component within your battery fails due to a defect in materials or workmanship within the 12-year warranty period, we will repair or replace the battery at our cost." Included accessories carry a 1-year warranty per BigBattery, and BigBattery provides free lifetime tech support for all its products.

Inverter — EG4 10-year warranty. Per EG4, the 18kPV carries a "10-year Full Parts Replacement or Full Product Replacement Warranty from the date of original inverter purchase," and the warranty must be registered within the first year of purchase (or proof of purchase from an EG4 authorized distributor provided) to remain valid.

Returns and warranty claims require an RMA. Contact us before shipping anything back — all returns must be authorized with a Return Merchandise Authorization first. OffGrid Horizon is a family-owned authorized BigBattery partner: call (302) 496-3554 and we will help open the claim and coordinate service.

Shipping

This kit ships as palletized LTL freight within the continental United States; curbside liftgate delivery is standard for residential addresses. ETHOS towers are heavy — 273 lb for a two-module stack per BigBattery — so plan for help on delivery day. Before signing the delivery receipt, count the pieces and inspect the packaging; note any damage or shortage on the receipt with the driver and contact us immediately so we can open a freight claim. Per BigBattery, standard domestic orders are projected to take 7–12 days to deliver.

Frequently Asked Questions

What exactly ships at the listed price?

This listing covers the EG4 18kPV inverter plus ETHOS battery storage configurable from 10.24 to 30.72 kWh. Call (302) 496-3554 before ordering and we will confirm the module count, included accessories, and any configuration options for this SKU.

Can it sell power back to the grid?

Yes — per EG4, the 18kPV supports grid export and is UL1741 SB listed with CSIP compliance. Export always requires an approved interconnection agreement with your utility.

Will this back up my whole home?

It depends on your loads. 12 kW of continuous output covers most household circuits, and pairing with the EG4 GridBOSS adds smart-load and generator management — but whole-home coverage is load-dependent and should be confirmed during design.

Does it work without solar panels?

Yes. The system operates as grid-charged battery backup, and panels can be added later — the 18kPV accepts up to 18 kW of PV, per EG4.

Can I add more battery later?

Yes. ETHOS is a stacking platform — per BigBattery, up to 16 parallel connections per control box — so capacity grows in 5.12 kWh steps without replacing the inverter.

Do the battery and inverter communicate?

Yes — per BigBattery, ETHOS runs closed-loop communication with compatible EG4 inverters over CAN bus for coordinated charging and accurate state-of-charge reporting.

Will the battery charge in freezing weather?

Per BigBattery, the ETHOS charge temperature range is 32°F to 113°F; the BMS restricts charging below freezing, so install the tower in an insulated or conditioned space in cold climates.

Not sure which capacity fits your home? Call OffGrid Horizon at (302) 496-3554 — we're a family-owned authorized BigBattery partner and will help you size the system before you order.

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