Like governmental entities, certain 501(c)3s are permitted to issue tax-exempt debt. Because interest earnings are not subject to federal taxes, tax-exempt bonds are issued with relatively low coupon rates producing significantly lower capital costs than taxable issues. To match the power purchase agreement and turbine useful life, the amortization for a tax-exempt financing would be between 15 and 20 years. Similar to a taxable variable rate issue, a letter of credit from a credit worthy commercial bank may be used provide credit enhancement. With a standard tax-exempt issue, the developer would not be eligible to receive production tax credits. However, it is possible to utilize a "flip" structure where taxable bonds are issued to enable the equity investor, who will have 99% ownership, to receive PTC and accelerated depreciation benefits. At year ten, there it is possible to flip ownership to the non-profit. The non-profit will assume 99% ownership and the project could be refinanced using tax-exempt bonds. This ownership offers the benefits of the tax benefits associated with renewable energy projects and the benefits of low cost tax-exempt financing.