If the events in 2020 have taught us anything, it’s to not take anything for granted. I know that after taking a hard look one of the things that I took for granted was power. I utilize power in every facet of my day-to-day life. Everything from charging phones, laptops, heating & cooling, refrigeration and lighting. Now that many people, including myself, are working from home, our home power is also tied to the ability to work and support our families. Having grown up in the power industry and a background in mechanical engineering & control systems, I took a hard look at the options to diversify our home power system. Regardless, if you are looking to have a full residence standby power system, partial standby system or just a UPS to power a few critical devices; understanding options and managing your expectations are critical.
Everyone’s power requirements are different, but the common requirement is the ability to decouple from the grid and therefore gain stability by diversification. The level of diversification and the size of the system dictates the how expensive the project will be. For example, if you seldom have power outages, live in a temperate climate, and only need to charge a few phones, keep the wifi running and power a few lights a few basic UPS’s will probably take care of what you need for a few hundred dollars. On the other hand, if you are looking for a 30 KW whole home auto switch over standby system it can be very expensive. The following series of articles will provide you with the steps and factors we took into account for building a basic partial load stand by generator with UPS’s for what we deemed as critical loads and ultimately we will incorporate solar generation for low load applications such as night time operation to minimize run time on the generator and the noise from the gas generator.
The first thing to always consider when weighing options and making decisions is safety. This includes making sure that whatever alternative power sources utilized are isolated to prevent energy from backfeeding into the line and the ability to isolate the system in a secure way to ensure zero energy during any work or maintenance on the system. Your local codes and building requirements should be reviewed as well to ensure compliance with your codes and regulations.
Keep in mind that this will be a system that has to work together therefore the sizing of the system must match the loads and the type of alternative system(s) selected must match the environment. We are in Oklahoma where the climate is mostly temperate, and we have suitable space to allow for a solar system or a gas powered generator. We don’t have much of an issue with noise restrictions or location requirements but unfortunately, we do have issues with ice storms and down powerlines.
When deciding how you’re going to incorporate your alternative generation systems, there are three main types of tie in’s recommended:
- Main Breaker Mechanical Interlock
- Manual Transfer Switch
- Automatic Transfer Switch
Transfer switches allow you to de couple from the grid and prevent a backflow of current to anyone working on the grid. We will discuss the types and benefits of each type of transfer switches in future. One tie in that is not recommended is to plug into a circuit with a double ended male plug and back feed through the receptacle, through a breaker in the panel to the rest of the house.
Planning our System
During the planning phase, several avenues were assessed. The following criteria were important for our installation:
- The generator needed to be capable of the loads outlined below:
- qty 2 refrigerator/freezer to prevent food spoilage
- The heater & circulation fan to heat the house
- Miscellaneous lights through the house approximately 8 or more lights
- The TV & stereo
- Fireplace ignition
- Coffee Maker
- Garage door opener
- Qty 3 ceiling fans
- The generator needed to have an electric start
- 120/240 VAC with a twist lock plug
- The generator needed to have a positive feedback on reliability and access to spare parts
- The generator needed to have a tri fuel or the availability of a tri fuel conversion kit
- A budget build utilizing a portable generator
- Ability to adapt a remote start/stop and monitor load & maintenance records
- Housed outside to prevent having to dig out the generator and hook up to the house.
The goal of the build is to document power diversification of a common household. Once the groundwork is laid out to decouple the house, various power generation methods can be utilized and the more aware owners will be of power consumption.
Follow us through the journey of diversifying our home power grid first through a common gas-powered generation system!