Micro Hydropower Spreadsheet Tool User’s How-To Guide
Kaita Albanese, Student, Bard MBA in Sustainability
Don’t let the words “financial model” frighten you, this excel tool is intended to be used by everyone, 来自那些对微水力发电站的数据有好奇心的人, 一个已经有了现有微水力发电站的技术规格，并希望测试项目有效性的专家. Using this interactive tool, 您可以探索各种“如果”的场景，并准确地调整假设的变化. Key issues to be determined include:
One: What is the size of your system?
Kilowatts are a measure of power. 一个能产生5千瓦到100千瓦电力的水力涡轮机被认为是“微水力”.” The size of the system, 结合河流的年度水头和流量估计, 将决定您的微型水电安装可以产生的收入.
Two: Do you know your total system cost?
The total cost of your system includes: design, permitting, legal support, ecological analysis, equipment, labor, permitting, interconnection, etc. 现代家庭使用的全安装水力系统的平均价格可能为20美元,000 to $100,000 or more. 但是，把这些数字仅仅看作可能成本的一般范围是不明智的. 系统的成本取决于您选择的特定技术组件, and the permitting process that you face.
Three: How much energy will your system produce?
微水力系统产生的能量与其最佳铭牌(系统在24/7完美流动条件下产生的能量)之间的比率称为其容量因子. In other words, 在季节性变化的流量条件下，你的涡轮产生的效率是多少? 水轮机的平均容量系数约为40%. 将涡轮机的大小与当地的水流设置相匹配是优化能源输出的关键——一个全年运行的小机组可能比一个充分利用春季融水和秋季降雨的大机组产生更多的能源.
Four: How long will your turbine operate? How much maintenance will it require?
Annual production degradation and turbine life, depreciation, and operations and maintenance costs, and turbine life are all dependent on several factors; some of these factors are controllable, like the quality of your turbine, and others are not, like damaging weather patterns. But also simple tasks like cleaning the trash rack in the fall need to be considered; the more the dam owners can do themselves, 他们需要雇佣的人越少，他们每年的运营和维护费用就越少.
十大外围足彩网站app假设在标准天气条件下，一个微型水轮机将在0退化.10% annual rate. 这对太阳能电池板是有利的，太阳能电池板的退化速度接近于0.50%. Additionally, 电子表格假设水轮机的使用寿命为30年, at least. 维护良好的涡轮机可能会持续更长时间.
由于场地条件的变化，很难估计操作和维护成本. We typically rate costs on a $/kW/Year basis. To give yourself some wiggle room, 十大外围足彩网站app建议您将您的年度运行和维护成本因素设置得尽可能高.
Five: How are you going to finance your system?
这个excel工具可以让你以任何百分比的现金或信贷融资-你可以玩弄贷款利率和期限, as well as your own assumed discount rate. We recommend an 8% discount rate, 考虑到这是你可能获得的平均回报如果你把钱投入股市而不是投资于你家后院的可再生能源项目.
Six: Review your results!
Once your cost and revenue estimates are in place, 十大外围足彩网站app来到了激动人心的部分:让这个微型水电系统为你发生的数字很重要.
当投资者需要对项目进行比较并决定投资哪个项目时, 一般有三种选择:内部收益率, simple payback, and net present value.
Additional Terms
Net Present Value, also known as NPV, is the tool of choice for most financial analysts. 它是一种将今天的投资金额与未来投资现金收入的现值进行比较的计算. In other words, 投资的金额与未来的现金金额进行比较后，他们被一个特定的回报率折现. 在这种情况下，回报率是您假设的客户折现率.
If the NPV is negative, it means that under the assumptions you made, the project will ultimately lose you money. But, if it’s positive, it will earn money. 正数越大，对钱包的好处越大.
Simple payback is another useful measurement. 就像它看起来的那样:你需要多少年才能收回最初的投资. For example, if you invest $100,000 initially, and make $20,000 back each year for 5 years, 你的回收期将是5年，因为你将在那一点(20美元)收支平衡,000 x 5 = $100,000).
Lastly, in making an investment decision, one can consider the project’s Return on Equity, or sometimes known as its internal rate of return. 在这个利率下，所有现金流(无论是正的还是负的)的NPV都等于零. 您希望这个比率大于您的客户折扣率. 如果它低于你的折现率，那么你很可能不会获得你想要的回报. 这并不能保证你的小水电站点在你选择的条件下不具有经济上的可行性. Look at your NPV number, and if it’s positive, 你会想要更深入地看看你的年度现金流，弄清楚到底发生了什么.
当你回顾你的成绩时要记住一件重要的事情: NPV takes precedence over the other measures. 一个净现值为负但内部回报率为正的项目在财务上是不可行的, 而净现值为正而内部收益率为负的项目则可以进一步考虑.
