The Bottom Line: is a 7KW System Right for Your Tiny House?

A 7kw solar system for tiny house setups is a practical choice when roof or ground space allows and when daily energy needs fall in the 12–30 kWh range or when owners plan to run a heat pump, induction cooking, or occasional EV charging. Choose a smaller system plus efficiency upgrades if roof area, budget, or simple daily loads make a large array unnecessary. Scale up if multiple heavy loads or multi-day autonomy are required.

How many panels do I need for a 7 kW system on a tiny house?

Panel quantity depends on module wattage. With 350 W panels you need about 20 modules (7,000 ÷ 350). With 400 W modules you need roughly 18 panels. Account for spacing, tilt, and roof obstructions when laying out the array; typical panel area is 1.6–2.0 m² per module, so plan for roughly 35–40 m² total footprint for 20 mid-size panels.

What size battery do I need with a 7 kW array?

Decide how many days of autonomy you want, then use: battery kWh = days of autonomy × daily kWh ÷ usable depth-of-discharge. For example, one day of autonomy for an 18 kWh/day load at 80% usable DoD needs about 22.5 kWh nominal capacity (round up to a 24 kWh bank). Many tiny houses use 6–20 kWh usable battery banks; LiFePO4 chemistry is common for space-constrained, long-life installs.

Will a 7 kW system fit on a tiny-house roof?

Sometimes. A 7 kW array usually needs 17–20 panels, which translates to roughly 32–40 m² of clear roof area depending on panel size. If roof area is tight, consider higher-wattage modules, split arrays across multiple roof facets, or a small ground/pole mount. Assess shading and structure first using a site checklist to avoid surprises.

Do I need a special inverter with a 7 kW array?

Choose an inverter based on expected simultaneous loads, continuous and surge ratings, and whether battery integration is needed. For many tiny houses, a 5–8 kW hybrid inverter works well; ensure the inverter’s surge capability handles heat-pump or motor starts. If shading is an issue, microinverters or power optimizers can improve energy harvest per panel.

What permits and inspections should I expect?

Expect to pull an electrical permit and often a building permit for rooftop attachments and battery installations. Inspections typically include PV electrical, structural attachments, and battery location/venting (if required). Check local AHJ guidance early and prepare single-line diagrams and equipment cut sheets for permit review. Santa Cruz County’s off-grid requirements are an example of local rules for array and battery minimums (see their guidance at Santa Cruz County off-grid solar requirementsSystemBatteryPermits/Off-GridSolarDesign/Off-GridSolarRequirements.aspx).

7KW Solar System for Tiny House: Complete Sizing Guide

Sustainable Building

A practical, step-by-step guide to sizing a 7kW solar system for a tiny house — panels, batteries, roof space, costs, and an example build.

By Graham Mann | Published: 6/17/2026

7KW Solar System for Tiny House: Complete Sizing Guide A 7kw solar system for tiny house owners can supply daytime power, run a heat pump or induction cooktop for much of the year, and provide meaningful battery-backed autonomy. This guide walks through estimating loads, choosing panels and batteries, calculating roof space, sizing inverters and charge controllers, and a worked example for a realistic tiny-house build. Read on to learn exactly how a 7 kW array performs in different climates, what components you need, and when a 7 kW array is more than you need. !Installers fitting rooftop solar panels on a tiny house in Oregon, illustrating a 7kw solar system for tiny house TL;DR: - A 7 kW array typically produces 21–35 kWh/day before storage, depending on 3–5 peak sun hours and system derate — enough for many modern tiny houses using heat-pump HVAC and efficient appliances. - Estimate battery capacity as: desired days of autonomy × daily kWh ÷ usable depth-of-discharge (example: 1 day...

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