Chapter 2. Investment needs and challenges 1970 and 2024. This reflects the nascent status of interconnectivity of the South today, but also the much higher need for capital-intensive subsea HVDC projects time horizon, which would add to future investment needs. As historical investment historical investment which was mainly for generation-to-grid projects, grid-to-grid projects make up the majority of investment, about USD 16 billion, over the next 15 years. The remaining USD 11 billion of investment is for generation-to-grid Lao PDR to Thailand and Viet Nam, solar exports from Indonesia to Singapore,