Understanding How Solar Owners Get Paid and Save on Electricity Bills

1. Introduction

For residential and commercial solar system owners, one question matters most: How do I get paid for the electricity my system generates?

The most common grid-tied solar model worldwide is "Self-Consumption + Surplus Feed-in" (also known as net billing or feed-in tariff with self-use). This model allows owners to use solar electricity directly, sell excess power to the grid, and dramatically reduce electricity bills.

This guide explains the settlement mechanism, calculation methods, and step-by-step in clear, practical terms.

2. What Is "Self-Consumption + Surplus Feed-in"?

Term	Definition
Self-Consumption	Electricity generated by your solar system that you use immediately in your home or business.
Surplus Feed-in	Electricity your system generates but you do NOT use immediately; it flows automatically to the utility grid.
Settlement	The utility company measures how much you consumed from solar vs. exported, then calculates your bill credit or payment.

Simple analogy: Your solar system is like a small power plant on your roof. First, it supplies your own needs. Anything extra is "sold" to your neighbors through the grid.

3. Key Commercial Parameters

3.1 Retail Electricity Rate (Import Price)

The price you pay to buy 1 kWh from the grid

Typically $0.10 – $0.35/kWh depending on country and time-of-use

Higher rates make self-consumption more valuable

3.2 Feed-in Tariff (Export Price)

The price the utility pays you for 1 kWh of surplus solar electricity

Usually lower than retail rate (e.g., retail $0.15 → FiT $0.05–0.10)

Some countries offer net metering (1:1 credit – retail = export price)

3.3 Net Metering vs. Net Billing

Model	Export Credit	Typical Location
Net Metering	1:1 – export credited at full retail rate	US (some states), Canada, parts of Asia
Net Billing	Export credited at lower feed-in tariff	Europe, Australia, China, most of world

Net metering is more favorable to solar owners because every kWh exported offsets a kWh purchased at the same price.

4. Step-by-Step Settlement Process

Phase 1: Before Installation

Check local regulations – What is the feed-in tariff rate? Is net metering available?

Apply for grid connection – Submit system size, inverter specs, single-line diagram

Utility approval – Utility confirms technical feasibility and meter requirements

Phase 2: Installation & Metering

Install solar system – Panels, inverter, racking (Longsun Green mounting solutions)

Replace or configure meter – Install bi-directional (import/export) meter

Utility inspection – Safety and compliance check

System commissioning – Permission to operate granted

Phase 3: Operation & Billing

Meter records data – Typically every 15–30 minutes or monthly

Utility calculates – Import kWh, export kWh, net consumption

Bill generation – Monthly or bi-monthly statement showing:

Total solar generation

Self-consumption (calculated, not directly measured)

Surplus export

Savings and credit

Payment or credit carryover – Excess credits may roll to next month or be paid out annually

Phase 4: Annual True-up (Some Markets)

In net metering systems, an annual true-up reconciles cumulative credits

Excess credits may be paid at a lower "avoided cost" rate

Some utilities reset credits to zero annually

5. Practical Example – Residential System

System: 5 kWp rooftop solar
Location: Assume net billing model (FiT = 60% of retail rate)
Monthly solar generation: 600 kWh
Monthly household consumption: 500 kWh

Time Period	Solar Generation	Household Use	Self-Consumption	Export to Grid	Import from Grid
Daytime	600 kWh	300 kWh	300 kWh	300 kWh	0 kWh
Nighttime	0 kWh	200 kWh	0 kWh	0 kWh	200 kWh
Total	600 kWh	500 kWh	300 kWh	300 kWh	200 kWh

Financial Calculation:

Item	Calculation	Amount
Retail rate	$0.15/kWh	-
Feed-in tariff	$0.09/kWh	-
Savings from self-consumption	300 kWh × $0.15	$45 saved
Income from export	300 kWh × $0.09	$27 earned
Cost of grid import	200 kWh × $0.15	$30 paid
Net bill without solar	500 kWh × $0.15	$75
Net bill with solar	$30 – $27 – $45? Let me correct:
Correct calculation:
Grid import cost	200 kWh × $0.15 = $30
Export income credit	– 300 kWh × $0.09 = –$27
Final bill	$30 – $27 = $3

Result: Monthly bill reduced from $75 to $3 – a 96% reduction.

6. Factors That Maximize Your Returns

Factor	Impact on Self-Consumption	How to Optimize
Daytime load	Higher daytime usage = more self-consumption	Run appliances (washer, dryer, EV charging) during sunlight hours
Battery storage	Stores excess for night use	Add battery to increase self-consumption from 30% to 70%+
System sizing	Oversizing may increase export (lower value)	Size system to match daytime load profile
Roof orientation	Affects generation timing	East-west arrays extend generation hours
Load shifting	Move consumption to sunny hours	Smart timers, water heating during midday

7. Settlement Timeline by Country (Typical)

Country	Typical Model	Settlement Frequency	Credit Carryover
USA (CA, NY, MA)	Net metering	Monthly	Annual true-up
Germany	Net billing	Monthly	Paid annually
Australia	Net billing	Quarterly	Paid quarterly
China	Net billing (FiT)	Monthly	No carryover
UK	Smart Export Guarantee	Monthly	Varies by supplier
India	Net metering	Monthly	Annual settlement

8. Common Pitfalls & How to Avoid Them

Pitfall	Consequence	Solution
No bi-directional meter installed	Utility cannot measure export; you get no credit	Confirm meter type BEFORE installation
Feed-in tariff lower than expected	Longer payback period	Get written FiT confirmation from utility
Self-consumption too low	Most energy exported at low FiT	Add battery or shift loads to daytime
Annual true-up pays at low rate	Large credits lost	Size system correctly; avoid oversizing
Utility approval delays	System sits idle for months	Submit application early; work with experienced installer

9. Why This Matters for Longsun Green Customers

As a solar mounting structure manufacturer, Longsun Green focuses on the physical foundation of your PV system. However, understanding settlement models helps you:

Right-size your system – Avoid oversizing that leads to low-value export

Choose optimal orientation – East-west arrays may better match daytime load profiles

Plan for battery integration – Longsun Green's adjustable racks accommodate battery systems easily

A well-mounted system + smart consumption strategy = maximum financial return.

10. Frequently Asked Questions (FAQ)

Q1: Do I need a special meter for surplus feed-in?
Yes. A standard meter cannot measure export. You need a bi-directional or net meter.

Q2: Can I see my self-consumption in real time?
Yes, with a monitoring system (e.g., inverter app, smart meter portal).

Q3: What happens to surplus export during a power outage?
Grid-tied inverters automatically shut down for safety. No export during outages unless you have battery backup with islanding capability.

Q4: Is self-consumption always better than exporting?
Almost always, because retail rate > feed-in tariff. Prioritize using your own solar power.

Q5: Does Longsun Green help with utility applications?
We provide mounting layout drawings and structural calculations needed for permit applications. Local installers typically handle utility paperwork.

Q6: Can I switch from net billing to net metering?
Only if your utility offers both models. Check local regulations.

11. Conclusion

The "Self-Consumption + Surplus Feed-in" model is the foundation of rooftop solar economics worldwide. Understanding how settlement works empowers you to:

Maximize savings by increasing daytime self-consumption

Avoid costly mistakes (wrong meter, oversizing)

Accurately calculate payback periods

Make informed decisions about battery storage

Key takeaway: Every kWh you self-consume saves you the full retail rate. Every kWh you export earns you the feed-in tariff. Prioritize self-consumption for the best returns.