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- $600 buys roughly 180-400 W of certified plug-in solar in the US.
- Small kits have a higher cost per watt but fit any outlet and the lightest legal tiers.
- Expect $30-150 a year in savings depending on your electricity price and sun.
- A DIY kit from separate components can be cheaper, but check certification requirements first.
Not everyone wants to spend $1,000 on an experiment. The good news: a small kit is a genuinely useful start, and in several states it is also the easiest to install legally.
In this article
What $600 buys
| Option | Size | Price (approx.) | Notes |
|---|---|---|---|
| Bright Saver 180 W | 1 glass-free panel | $285 (member) / $499 | Certified microinverter; very light |
| Bright Saver 360 W | 2 glass-free panels | $414 (member) / $499 | Under the 391 W threshold in some states |
| Modular 400 W kit | 1 glass panel | ~$600-650 | More output per dollar; heavier |
| Component build | 1-2 panels + certified microinverter | $400-600 | Cheapest per watt; you handle compatibility |
US prices reported in 2026. Membership pricing refers to Bright Saver’s $29/year membership.
What will it save?
A 360-400 W kit produces roughly 300-600 kWh a year depending on location and mounting. Because it is small, almost all of it is used at home.
| Electricity price | ~400 kWh/year used | Payback on a $450 kit |
|---|---|---|
| $0.13/kWh (Pacific NW, Utah) | $52/year | ~8-9 years |
| $0.18/kWh (US average) | $72/year | ~6 years |
| $0.30/kWh (New England, CA) | $120/year | ~4 years |
Plug your figures into the calculator.
Building your own kit
A panel plus a microinverter can cost less than a packaged kit. If you go this way:
- Choose a microinverter with the certification your state requires (see UL 3700 list), a 120 V output and a factory-fitted plug cable.
- Check the panel’s voltage and current fit the inverter’s input range.
- Use proper MC4 connectors; never improvise.
- Buy a rated mount. Cheap mounting is where DIY builds most often fail.
Our microinverter guide helps with compatibility.
Is small worth it?
Yes, if you see it as a first step. You learn how much your balcony produces, you face minimal legal hurdles, and you can add a second panel later where the law and your landlord allow. See small kits
Where the money goes in a small kit
| Component | Share of cost (approx.) |
|---|---|
| Microinverter | 30-40% |
| Panel(s) | 30-45% |
| Mounting hardware | 10-20% |
| Cables, shipping, packaging | 5-15% |
That is why a small kit costs more per watt: the inverter and mounting cost roughly the same whether you attach one panel or two.
Frequently asked questions
Can I start with one panel and add a second later?
Yes, if the microinverter has two inputs and your state’s cap allows the total. Buy a two-input inverter from the start to keep that option open.
Are used panels a good idea?
Used panels can be cheap and still productive, but check for cracks, hot spots and that the specifications suit your inverter. Never compromise on the inverter’s certification.
Is a $200 marketplace kit OK?
Be careful. Very cheap kits often lack verifiable certification or ship with inverters built for other countries.
Sources
- Balcony solar kits, Bright Saver.
- $29 membership, Bright Saver.
- Bright Saver begins offering plug-in solar kits at wholesale costs nationwide, pv magazine USA.
- Electricity rates by state (EIA data, June 2026), Choose Energy.
Sources checked in September 2026. Laws, prices and product details change; if you spot something out of date, tell us.