No one should turn down wind farming’s ultimate passive income for the next 30 or more years … even 60 years when there is a positive cash flow on the sum total of all base payments when computing inflation for the next 60 years based on the previous 60 years, as long as the next era’s energy resource is not perfected (at which time they would not renew the option for the second 30 years).
There are three main categories of income: active income, passive income and portfolio income. Passive income has been a relatively loosely used term in recent years. Colloquially, it’s been used to define money being earned regularly with little or no effort on the part of the person receiving it. Popular types of passive income include real estate, peer-to-peer (P2P) lending and dividend stocks. Proponents of earning passive income tend to be boosters of a work-from-home and be-your-own-boss professional lifestyle. The type of earnings people usually associate with this are gains on stocks, interest, retirement pay, lottery winnings, online work and capital gains. 
Greg Johnson is a personal finance and frugal travel expert who leveraged his online business to quit his 9-5 job, spend more time with his family, and travel the world. With his wife Holly, Greg co-owns two websites – Club Thrifty and Travel Blue Book. The couple has also co-authored a book, Zero Down Your Debt: Reclaim Your Income and Build a Life You'll Love. Find him on Instagram, Facebook, and Twitter @ClubThrifty.
So, if the goal is to have residual income when we retire, which seems based on Social Security rules to only be possible in our 60’s, and the government has mandated penalties before taking our money before 59.5, wouldn’t it be prudent to start investing in sources of residual income now that maybe don’t have an age limit into our 60’s? What guarantee do we have that we will make it that long?
Managerial accounting defines residual income in a corporate setting as the amount of leftover operating profit after all costs of capital used to generate the revenues have been paid. It is also considered the company's net operating income or the amount of profit that exceed its required rate of return. Residual income is normally used to assess the performance of a capital investment, team, department or business unit.