ASEAN is a region with high carbon dioxide (CO2) emissions, accompanied by an increase in population, gross domestic product (GDP) and energy consumption. Population, GDP, and energy consumption can be linked to CO2 emissions through an identity equation called the Rich Identity. This research is based on Kaya identity to describe CO2 emissions to calculate the impact of population, economic activity, energy intensity and carbon intensity on CO2 emissions in ASEAN and 8 ASEAN countries (i.e., Indonesia, Malaysia, Singapore, Thailand, Philippines, Vietnam, Myanmar and Brunei Darussalam) from 1990 to 2017. The method used is the Logarithmic Mean Division Index (LMDI). The data used are from the International Energy Agency (IEA) and the World Bank. Four effects measured and main findings showed that population, economic activity and carbon intensity factor increased by 293.02 MtCO2, 790.0 MtCO2, and 195.51 MtCO2, respectively. Meanwhile, energy intensity effect made ASEAN's CO2 emissions decrease by 283.13 MtCO2. Regarding contributions to the increase in CO2 emissions in all ASEAN countries, the population effect increases CO2 emissions in all countries in ASEAN and the economic activity effect is also the same, except in Brunei Darussalam which makes CO2 emissions in this country decreased by 1.07 MtCO2. Meanwhile, the effects of energy and carbon intensity are different. The effect of energy intensity causes CO2 emissions in lower-middle income countries to decrease, while in upper-middle and high-income countries, it increases carbon emissions. In contrast to the effect of carbon intensity, that actually makes CO2 emissions increase in lower-middle income countries and reduces carbon emissions in upper-middle and high-income countries.

Highlights • Individual investors prefer to have an investment with high ROI rather than a low-profit investment with environmental and social benefits. • Males invest and donate more money than females in terms of quantity and frequency. • People with a level of education above an associate degree (D3) have a significantly higher level of willingness to invest and donate to green project, compared to people with a lower level of education. • In general, people with a higher income level have a higher willingness to invest. However, there is no proof on the relationship between level of income and willingness to donate. • The age increases have a positive correlation with the willingness to invest in green project. Nevertheless, people >44 years old are more interested in donating than investing. • The younger generation (<44 years) tends to pick higher returns and short payback periods compared to the older generations (>44 years). • The respondents tend to invest and donate to the project located in the frontier, outermost, and least developed region (3T) even though the majority of the respondents are from Java, Madura, and Bali. • A social project such as health and education are preferable projects chosen by the respondents to invest and donate to, followed by the conservation, climate crisis, region’s welfare, and clean energy access. • Clean energy has not been seen as one of the preferred targets for green project investors and donors due to the poor knowledge of its direct impact on the environment and people’s welfare. • The average willingness to invest and donate is IDR 10,527,004 and IDR 2,893,079/person/annum with desired return on investment (ROI) and payback period (PP) of 5–8% 24 months, respectively. • Respondents prefer to donate more money to reward donations than donations without reward. • There is an enormous potential of crowdfunding as green project alternative financing, including renewable energy. The total investment could reach up to IDR 192 trillion (USD 13.4 billion)/annum and up to IDR 46 trillion (USD 3.2 billion)/annum for donation. • The main bottlenecks are poor financial literacy and the lack of platforms to facilitate public participation. • COVID-19 has decreased willingness to pay and invest due to income reduction and the uncertain economic recovery situation. However, it makes people pay more attention to the sustainability factor (shifting paradigm in investment).