Micro-Hydro

If you are one of the lucky few with a usable water resource, harnessing the energy in a stream or creek can be the most cost effective way to make renewable electricity. Because a stream’s flow is relatively constant, the output of a microhydro system is 24/7 and produces a very dependable supply of electricity that adds up quickly. Unlike large scale hydro projects, well conceived microhydro systems do not require large reservoirs and have minimal impact on the ecosystem in which they are placed.

A wide variety of equipment and configurations are available to match the site conditions. However, the two things every system needs to make power are head and flow. In a typical “high head” installation, a pipe moves water from a high point where water is collected to a low point where a small turbine is located to generate power. The vertical distance between these two points is the gross head. The minimum head for most microhydro generators is 20-30 feet (depending on the length of the pipe) which creates a pressure of about 10 psi at the outlet. Generators that operate with very little head are also available, but require much more flow (around 100 gallons per minute).

Before contacting us to install a microhydro system it is a good idea to do a bit of investigating to get a rough idea of head and flow in order for us to determine feasibility at your site. Home Power Magazine is an excellent resource for understanding the basics of microhydro and how to determine head and flow. Click here to check out Home Power Magazine.

Once we have determined that microhydro may be feasible for your location Arvak can do a thorough site evaluation. During a site evaluation we will walk the stream and property to determine the best site for the pipe run, hydro generator and other equipment required to store and use the generated electricity. Available head and estimated flow rate will be confirmed to design the optimal system for your resource. We will also assess how to couple hydro power generation in the context of an off-grid or grid-connected renewable energy system. Hybrid systems incorporating PV in addition to microhydro can be designed to be grid-connected and may qualify for incentives. A typical system (with inverter, batteries, and code compliant safety equipment) can cost anywhere from $15K to $30K depending on the amount of labor required for installation.