Installation manual

2. Step by step design overview

This section briefly outlines the main choices you will need to make in the design of your

system and ordering the delivery.

2.1. Survey your site

Section 4 describes how to measure the head and flow of your hydro power site. You will

also arrive at a length for the "penstock" or pipeline between the intake and the turbine site,

and the length of the cable to your point of use. Take this information to the online

Advanced Calculator or to a dealer. You will learn how much energy to expect from the

turbine and what size of pipe you will need. Once you have decided the best layout you may

need to get permissions, and take more accurate measurements before proceeding.

2.2. On or off-grid electrical system?

If you are able to connect to the utility grid and it is reliable then we strongly recommend that

you choose an on-grid system without batteries. This will be simpler, cheaper and more

environmentally friendly. Batteries need careful attention, and regular expensive

replacement.

If you are on-grid then you can ignore large parts of this manual that deal with the various

controllers required for battery systems. See section 5.14 for details of how to use a "grid-

tie" inverter to connect your hydro to the grid so as to save electricity bills.

2.3. Battery voltage choice

12 V batteries were popular for small renewable energy systems in the past, but nowadays

we see 48 V as a more practical choice. However the decision will depend on your needs.

Some very small systems may work better at 12 V because the battery is cheaper to buy

and some of the load equipment may itself be 12 V for example. 24 V offers some of the

advantages of each (and some of the drawbacks). Lower voltage systems are less efficient

on the whole due to higher losses in rectifier and wiring.

If you have an existing battery system then you will probably wish to add the turbine to this

system alongside the solar, wind or engine driven sources of energy that you already use.

2.4. Direct connection or MPPT?

PowerSpout turbines can be connected directly to the battery, and this can often be the

cheapest option. In this case make sure that you provide sufficiently for charge control of

the battery. This can be done using a "diversion load controller" or PWM controller (see

section 5.5.1). But there are drawbacks with direct connection of the turbine to the battery.

PowerSpout recommend connection via Maximum Power Point Tracking devices (controllers

and inverters) that have several advantages:-

 MPPT adjusts voltage automatically for maximum Watts output. This has two

advantages: you tend to get more power, and you don't have to manually tinker with the

turbine to optimise it. (You will still need to adjust the flow to suit available water.).

 Higher transmission voltage often results in significant cable cost savings.

 Generally fail-safe – in the event of controller failure generation stops so the batteries are

not damaged.

 The controller will display (and log) production data.

 Precise battery setting of bulk, float, EQ - this is often needed for battery warranty proof.