Cost-Benefit Analysis of Owning an Electric Vehicle for a Residential Home with Solar PV under Malaysia’s NEM Scheme

Abstract

The transition to electric vehicles (EVs) is accelerating globally, driven by environmental concerns and energy cost savings. This paper evaluates the cost-benefit of replacing a petrol (gasoline) car with an EV for residential users in Malaysia under the Net Energy Metering (NEM) scheme. A comparative analysis is conducted using Excel-based model for households with different electricity consumption levels (300 kWh, 500 kWh, 700 kWh, and 900 kWh per month) and varying daily EV commutes (20 km to 100 km per day). The study considers an 80 kWh EV car charged solely at home, with and without rooftop solar photovoltaic (PV) systems (4 kWp and 10 kWp). Results indicate that for low to moderate household electricity consumption (≤500 kWh/month), EV ownership remains cost-effective compared to petrol cars, even without solar PV. However, for high energy users (>700 kWh/month), additional EV charging pushes electricity bills into higher tariff blocks, increasing costs. Installing a 4 kWp or 10 kWp solar PV system significantly reduces charging costs, with a 10 kWp system eliminating grid electricity expenses almost entirely. Meanwhile, household with 4 kWp can save at least 52.32% up to 100% depends on electricity and EV consumption. Sensitivity analysis further reveals that higher electricity tariffs can reduce the cost advantage of EVs without PV, while rising petrol prices improve EV savings. Additionally, improvements in EV efficiency and PV generation enhance financial returns, making EV-PV integration a more robust investment under varying market conditions. Without PV, the financial advantage of EVs depends on fuel price stability and electricity tariff rates. This analysis highlights that EV adoption is most cost-effective when combined with solar PV, aligning with Malaysia’s energy transition goals.