Since 1 July 2025, TNB's domestic electricity bills follow the Regulatory Period 4 (RP4) tariff: an unbundled structure of Energy, Capacity, Network and Retail charges, with an Energy Efficiency Incentive for lower-use homes, instead of the old tiered blocks. For solar owners, the number that matters is simple: every kWh your panels supply at home avoids RM 0.4443 of charges (RM 0.5443 above 1,500 kWh a month), while every kWh you export earns only the Energy Charge, RM 0.2703. This guide shows the RP4 structure and what it means for your solar payback.
The RP4 Domestic Tariff Structure
The Domestic General tariff (from 1 July 2025) is no longer a tiered block tariff. You pay these charges on every kWh:
| Charge | Rate |
|---|---|
| Energy Charge | 27.03 sen/kWh (up to 1,500 kWh a month); 37.03 sen/kWh for all kWh if you use more than 1,500 kWh a month |
| Capacity Charge | 4.55 sen/kWh |
| Network Charge | 12.85 sen/kWh |
| Retail Charge | RM 10 a month (waived at 800 kWh or less until 31 Dec 2026; 600 kWh or less from 2027 unless extended) |
Energy Efficiency Incentive (EEI)
Homes using 1,000 kWh a month or less get a rebate that depends on total monthly use:
| Total monthly use | EEI rebate |
|---|---|
| 1-200 kWh | -25.0 sen/kWh |
| 201-250 kWh | -24.5 sen/kWh |
| 251-300 kWh | -22.5 sen/kWh |
| 301-350 kWh | -21.0 sen/kWh |
| 351-400 kWh | -17.0 sen/kWh |
| 401-450 kWh | -14.5 sen/kWh |
| 451-500 kWh | -12.0 sen/kWh |
| 501-550 kWh | -10.5 sen/kWh |
| 551-600 kWh | -9.0 sen/kWh |
| 601-650 kWh | -7.5 sen/kWh |
| 651-700 kWh | -5.5 sen/kWh |
| 701-750 kWh | -4.5 sen/kWh |
| 751-800 kWh | -4.0 sen/kWh |
| 801-850 kWh | -2.5 sen/kWh |
| 851-900 kWh | -1.0 sen/kWh |
| 901-1,000 kWh | -0.5 sen/kWh |
Time-of-Use, AFA, and Taxes
- Domestic Time-of-Use (ToU): Energy Charge of 28.52 sen/kWh at peak and 24.43 sen/kWh off-peak (up to 1,500 kWh a month); 38.52 / 34.43 sen above 1,500 kWh. Peak is 2pm-10pm, Monday to Friday.
- AFA (Automatic Fuel Adjustment): set monthly; homes using 800 kWh a month or less are exempt until 31 Dec 2026.
- Taxes: 8% service tax applies only to homes using more than 800 kWh a month; the 1.6% RE Fund applies except to homes using 300 kWh or less.
Source: TNB tariff schedule, 1 July 2025 to 31 December 2027, and the myTNB tariff portal.
What RP4 Means for a Typical Malaysian Household
Bill examples (before AFA, the RE Fund and service tax):
| Household Type | Monthly kWh | Energy | Capacity | Network | EEI | Retail | Bill |
|---|---|---|---|---|---|---|---|
| Small terrace (2 aircons) | 450 kWh | RM 121.64 | RM 20.48 | RM 57.83 | -RM 65.25 | RM 0 | RM 134.69 |
| Medium semi-D (3 aircons) | 700 kWh | RM 189.21 | RM 31.85 | RM 89.95 | -RM 38.50 | RM 0 | RM 272.51 |
| Large bungalow (4+ aircons) | 1,100 kWh | RM 297.33 | RM 50.05 | RM 141.35 | RM 0 | RM 10 | RM 498.73 |
Notice how the EEI cuts the bill for lower-use homes: at 450 kWh it takes RM 65 off, at 700 kWh RM 38, and above 1,000 kWh nothing. That is why a home's bill rises faster than its kWh as usage crosses 1,000 kWh.
How the RP4 Tariff Shapes Solar Payback
Your solar system saves money in two ways. Solar you use at home displaces grid electricity: that avoids the Energy, Capacity and Network charges, RM 0.4443/kWh (RM 0.5443/kWh above 1,500 kWh a month), though the EEI rebate changes as your total use falls. Solar you export under Solar ATAP is credited at the Energy Charge only: RM 0.2703/kWh (RM 0.3703 above 1,500 kWh), offset against your bill. Unused export credit is forfeited at the end of each billing period. To understand how self-consumption-first billing carried over from the old NEM 3.0 scheme into Solar ATAP, read our NEM 3.0 to Solar ATAP guide. For full details on the programme, see our Solar ATAP guide.
Key Principle: Solar is worth most when it replaces the full RM 0.4443 per kWh at home. Exported kWh are worth RM 0.2703, so size your system to your daytime use.
ROI Examples on the RP4 Tariff
Estimate on the RP4 domestic tariff (from 1 Jul 2025), before AFA, the 1.6% RE Fund and service tax; 3.5 sun-hours a day; about 40% of solar used at home and the rest exported and credited at the 27.03 sen Energy Charge (capped at what you import) for 10 years under Solar ATAP; no tariff increases. Your bill and roof will change the figures.
5.58 kWp System (RM 15,999, Solis), 739 kWh a Month (RM 300 bill)
| Metric | Value |
|---|---|
| Monthly generation | 586 kWh |
| Used at home (40%) | 234 kWh |
| Exported (60%) | 352 kWh x RM 0.2703 = RM 95 credit |
| Bill before solar | RM 300 |
| Bill after solar | about RM 116 |
| Monthly savings | about RM 184 |
| Payback period | about 7.2 years |
| 25-year savings | about RM 44,760 |
8.06 kWp System (RM 21,499, Solis), 1,070 kWh a Month (RM 550 bill)
| Metric | Value |
|---|---|
| Monthly generation | 846 kWh |
| Used at home (40%) | 338 kWh |
| Exported (60%) | 508 kWh x RM 0.2703 = RM 137 credit |
| Bill before solar | RM 550 |
| Bill after solar | about RM 230 |
| Monthly savings | about RM 320 |
| Payback period | about 5.6 years |
| 25-year savings | about RM 75,480 |
9.92 kWp System (RM 23,999, Solis), 1,351 kWh a Month (RM 700 bill)
| Metric | Value |
|---|---|
| Monthly generation | 1,042 kWh |
| Used at home (40%) | 417 kWh |
| Exported (60%) | 625 kWh x RM 0.2703 = RM 169 credit |
| Bill before solar | RM 700 |
| Bill after solar | about RM 327 |
| Monthly savings | about RM 373 |
| Payback period | about 5.4 years |
| 25-year savings | about RM 82,200 |
There is no 5 kW, 8 kW or 10 kW package in our catalogue; these are the nearest sizes.
Will TNB Tariffs Change Again?
Since July 2025 the old ICPT has been replaced by the Automatic Fuel Adjustment (AFA), set monthly from fuel prices and exchange rates, as determined by the Energy Commission. For October 2026 the AFA is +3.61 sen/kWh (TNB's forecast: November +4.27 sen, December +4.46 sen, January 2027 +7.59 sen). Homes using 800 kWh a month or less are exempt from AFA until 31 December 2026. The RP4 tariff schedule runs to 31 December 2027.
We assume no tariff changes in our examples. If charges rise, solar savings rise with them; if they fall, savings fall.
How to Get the Most from Solar on RP4
- Calculate your current bill baseline: Use our Solar Savings Calculator to enter your latest TNB bill and see your ROI projection at current RP4 rates.
- Size your system for your daytime use: If you plan to buy an EV or add an air conditioner, size for that demand; exported power earns less than power you use at home.
- Understand system cost: Read our complete solar panel cost guide for Malaysia 2026 to know what a fair installed price looks like for your system size.
- Check Solar ATAP eligibility: Under Solar ATAP, you earn export credits for excess electricity. Understanding how this works is critical for sizing your system correctly.
The Bottom Line on TNB RP4 and Solar ROI
Under RP4, solar used at home is worth RM 0.4443 per kWh and exported solar RM 0.2703. For homes with RM 300 to RM 500 bills, payback is about 5.2 to 7.2 years; bills under RM 200 take longer. Your own bill and daytime use decide it.
Use our calculator to see your personal numbers, or get a free quote from your bill. No site visit is needed to quote.
