With technological advances, the cost of solar panels has decreased over time. The cost of solar energy is now generally cheaper than the retail electricity price and regulated tariff. Hence, the Government does not provide grants or subsidies to further incentivize the adoption of solar energy. For energy efficiency grants, you may find out more about the Building Retrofit Energy Efficiency Financing (BREEF) scheme. You may also wish to visit BCA's BuildSG Transformation Fund webpage which lists the various schemes (apart from those related to energy efficiency financing), to see if there is any other suitable schemes for your project there.