DivestBU recently submitted a proposal urging Boston University’s Board of Trustees to divest BU’s endowment from all fossil fuel companies.

This is not some extreme, leftist idea. Divestment from fossil fuels is rational and necessary for the sustainability of our planet, and all universities should lead by example by refusing to invest money into corporations that pollute our environment.

Middlebury College and Seattle University have declared they will divest their endowments of fossil fuels. So why can’t Boston University?

The purpose of BU’s endowment is to provide income through investments to help fund the institution’s operations. BU’s endowment in Fiscal Year 2018 stood at nearly $2.2 billion, doubling its value since 2010.

In 2016, President Robert Brown sent a letter to the BU community stating the university would do its best to avoid investing in companies that extract coal and tar sands. The Board of Trustees also directed its Investment Committee to revisit the issue of divestment at least every five years as economic, climatic and technological developments may warrant.

Waiting every five years to consider divestment is ridiculous. Climate change is perhaps the most pressing issue of our time, and more and more information comes out every year about the dangers it poses.

Boston University must be transparent about which fossil fuel companies it invests in and how much it invests in them. This would include indirect investment through mutual funds and exchange-traded funds.

We agree with DivestBU that avoiding investment in only coal and tar sands companies fails the BU community. Passive divestment is not enough. BU must actively divest in all companies that currently extract fossil fuels.

DivestBU also asked the Trustees to “use the divested funds to establish a Green Economies fund.” This fund would not include any financial holdings in fossil fuel companies and would promote investment in companies pursuing green energy.

Although green investment funds in the past were associated with low returns on investment, in recent years more and more mutual funds and exchange-traded funds that are socially responsible have been introduced. They typically invest in renewable energy producers and suppliers, LED light bulbs manufacturers and battery technology.

These funds tend to have roughly equal or, at points higher, returns compared to standard mutual funds that invest partially in fossil fuels.

DivestBU also wants BU to allocate profits from the Green Economies Fund equal to 1 percent of the university’s current investments in fossil fuels into a Social Welfare Fund. While BU is a private institution, it is also a nonprofit whose mission must be to serve its students, alumni and the greater community.

Investing in affordable housing and locally based clean energy initiatives, which are both ideas introduced in DivestBU’s proposal, is important.

As an active organization that has been on campus for seven years fighting for a cleaner, safer environment, DivestBU is a true example of persistence, patience and dedication.

The Trustees must address DivestBU’s proposal. Waiting until 2021 to evaluate divestment is unjust and inequitable to the students of Boston University and the alumni who donate to the endowment year after year.