Why your post-solar TNB bill has an “EEI reversal”

What a unit of electricity costs – and your rebate

Every unit you buy from TNB costs about 44 sen: the energy itself (~27 sen) plus fixed grid charges (~17 sen) that apply to every unit you buy, solar or not.

There’s also a rebate on that energy charge, called the Energy Efficiency Incentive (EEI). It’s the government’s way of rewarding you for using less. If your home uses 1,000kWh or less in a month, money comes back on a sliding scale: the less you use, the bigger the rebate per unit.

A very light user (200kWh or less) gets the full 25 sen off every unit, so their energy works out to about 2 sen/kWh instead of 27 sen. The rebate shrinks as you use more, and disappears once you pass 1,000kWh a month. It’s applied automatically from your monthly usage – there’s nothing to claim. Keep it in mind: it’s the key to everything below.

Here’s what the EEI does to the energy rate you actually pay:

Each bar is the 27 sen energy rate. The EEi rebate (stripped pink) is what lowers it forlighter users – the less you use, the more comes off. until it runs out past 1,000 units a month. Grid changes of ~17 sen a unit sit on top and are the same either way.

Where your Solar Electricity goes

Your panels do two things: power your home with Solar Electricity during the day and sell the extra to TNB under Solar ATAP. When solar is not enough or at night, your home seamlessly draws electricity from TNB.

Using your own Solar Electricity is better

Let’s assume your home uses about 1,000kWh of TNB electricity a month before solar, and after using Solar Electricity it only buys roughly 700kWh from TNB, which puts it in the 5.5 sen rebate band. For this example: use 1kWh of Solar Electricity directly and you save its whole cost, about 44 sen. Sell it to TNB and you only save the energy part (27 sen), minus that 5.5 sen rebate.

Why the rebate comes off what you sell

The rebate is an incentive for buying less from TNB. So it only counts on TNB Electricity you actually buy, not on Solar Electricity you sell. Adjust the EEI and you’re left with a fair, one-for-one swap: you get credited at the same price you paid TNB.

If you buy the same amount of TNB Electricity as the Solar Electricity you sell, under Solar ATAP, your energy charges are zero.

A real month

Here’s a real month, before and after solar – only the energy part of your bill. Capacity, network and retail charges are the same either way, so solar doesn’t touch them.

The reversal is tiny next to what you saved.

Three ways to come out further ahead

1. Use Solar Electricity while the sun’s up. Run washing, water heating and aircon in daylight – that’s the “save everything” kind.

2. A bigger system helps. More generation means fewer units bought from TNB – cheaper straight away, and with the EEI, each unit you do buy is cheaper too (the rebate grows the less you buy).

3. Don’t oversize just to sell. Under Solar ATAP you can’t roll spare credits over to the next month, so any Solar Electricity you export beyond what your bill absorbs is simply wasted. Size the system to how your home actually uses electricity, not to a brochure number.