I've a friend who is certified ASHRAE and Energy Manager, he advise its not worth it now to get solar installed. Earlier yes.

I've calculated mine, ROI 7 years is just not worth it.

What we're thought, is that solar price will decrease and duration to ROI will decrease. This was correct, but the ROI heavily depended on the scheme provided by TNB. Last time, RM10~12k/kW now Rm4~5k/kW. Solar price did go down, but ROI was longer.

Moving forward, solar price will keep going down, or the technology gets better. Electricity tariff heavily depends on cost of fuel, and subsidy. Right now, fuel subsidy and electricity subsidy is going to cut. Biggest question will be, what is the NEM to discount ratio? The economics of solar will 'self balance' between solar vendors pricing vs TNB scheme. Otherwise, everybody will rush to installing solar and we end up like Australia.

In short, I foresee ROI will maintain between 7~10 years no matter the solar technology or pricing, unless something distruptive comes along.

Guys, if someone bought a house that the previous owner had installed some kind of power saving mod, I think it was at the the meter, will the new owner get in trouble when they want to install solar system at the house? They could not see anything wrong with the meter though.