Switching to solar energy in Singapore can lead to significant electricity saving on your electricity bills and even allow you to earn money by selling excess power back to the grid.
Generally, there are three main ways to do this: the Simplified Credit Treatment (SCT) scheme, which offers predictable credits based on quarterly SP Group rates and is ideal for residential users; the Enhanced Central Intermediary Scheme (ECIS), available to those signed on to Open Electricity Market (OEM) retailers, where credits are based on the fluctuating wholesale Uniform Singapore Energy Price (USEP), offering potentially higher but variable earnings; and the Market Participant (MP) scheme, specifically for larger commercial solar producers, allowing them to register directly with the Energy Market Company to sell electricity at market prices.
This guide will mainly discuss the SCT and ECIS schemes, breaking down how they impact your electricity savings efforts and how to make the best financial choices for your home.
How Solar Energy Reduces Electricity Bills
Solar panels produce electricity during the day by capturing sunlight, which powers your home and cuts down on your reliance on the grid, leading to electricity saving. This means less grid consumption during daytime hours.
As shown in this example chart from a solar inverter app, solar generation (green line) peaks around midday. The blue line indicates how much of this solar energy is directly used by your household. During the day, most of your home’s energy needs are met by solar. The surplus energy covers your household needs (red line), reducing how much need from the grid. Any extra solar energy not consumed is send back to the grid, earning you credits on your electricity bill and further lowering your costs.
In this example, your household used a total of 106.80 kWh of electricity. Of this, 51.27 kWh was covered by solar, reducing the electricity needed from the grid. The remaining 55.53 kWh was drawn from the grid, mainly at night when your solar panels weren’t producing. Meanwhile, your solar system generated 204.22 kWh for the day, with 152.95 kWh as surplus energy, which was sent back to the grid, earning credits.
You can track this with your solar inverter app to monitor energy production and consumption in real time. The app shows daily solar generation and how much energy is used versus what is exported. This insight helps you maximise savings by understanding your energy use patterns.
On your SP bill, you can find the “Export of electricity,” section showing credits earned by sending surplus energy to the grid. For example, if you exported 1256 kWh at a rate of $0.2342 per kWh, you would earn a credit of $294.16, which offsets the total owed for grid electricity.
Solar Sell-Back Options in Singapore
Homeowners in Singapore can maximise electricity savings by selling excess solar power back to the grid through two main schemes, depending on their home’s setup and energy provider.
- Simplified Credit Treatment (SCT) Scheme
The SCT scheme is designed for residential, non-contestable consumers—meaning you get your electricity from SP Group rather than OEM retailers. It offers a stable credit based on the quarterly tariff rate minus grid charges, which means you’ll receive about 75-80% of the rate. SCT is applicable only to residential installations with solar systems below 1 MWac. For instance, in Q3 2022, the SP Group tariff rate was $0.3017 per kWh (before GST). Under SCT, solar homeowners received a credit of approximately $0.2423 per kWh—approximately 80% of the tariff rate—enabling significant electricity savings.
- Enhanced Central Intermediary Scheme (ECIS)
ECIS is available for both residential and commercial users who buy electricity from OEM retailers rather than SP Group. ECIS applies as long as the system capacity is under 10 MWac. Credits are based on the USEP, which fluctuates every half hour according to market demand and supply. ECIS offers potentially higher earnings during peak periods but is more volatile, meaning that credits can vary significantly. Despite the fluctuations, it can lead to considerable electricity savings during high-demand periods.
Comparing SCT and ECIS: Choosing the Right Scheme for Electricity Saving
To decide on the best way to sell back your solar energy, it’s important to compare the export rates over recent years. Below is a summary of recent trends in USEP, which is the wholesale rate paid under the ECIS scheme, versus the stable rates offered by SP Group under SCT scheme.
In 2022, USEP prices fluctuated significantly, making ECIS particularly profitable for those exporting surplus solar energy. However, by mid-2022, prices dropped sharply to around $200/MWh, underscoring the unpredictability of wholesale rates. So far in 2024, USEP prices have been more stable, fluctuating moderately between $100 and $300/MWh.
Reference : SP Website
In contrast, SP tariffs have shown much greater stability. For SCT users, this translates into consistent and predictable credits, making SCT an appealing option for those who prefer consistent returns on their energy exports. However, there have been times when either USEP or SP rates offered better returns for solar exports, so it’s wise to periodically review which scheme maximises your electricity saving.
Making Informed Decisions on Electricity Saving, Solar Savings, and Sell-Back Options
When choosing how to save and earn from your solar energy, it’s essential to select a scheme that aligns with your financial goals and comfort with rate fluctuations. Currently, we recommend SP Group’s SCT scheme for its predictable rate based on SP’s quarterly tariff, which is generally higher and more stable. Given that wholesale USEP prices are low at present, the SCT scheme offers consistent and reliable returns. However, if you’re open to market fluctuations for the possibility of higher returns, consider the ECIS scheme with an OEM retailer. At GetSolar, we support our Rent-to-Own customers by providing a twice-yearly newsletter that tracks USEP rates helping customers decide when to switch schemes.
To maximise your electricity saving and get the most from your solar system’s sell-back options, reach out to GetSolar for guidance on choosing the best options for your solar needs.