Hot+Water+Heaters


 * **TASK STATUS REPORT** ||
 * **Project Description:** |||||||| To research the most energy efficient hot water system ||
 * **Project Sponsor:** Habitat for Humanity ||||  || Sponsor Rep: ||   ||
 * **Program Manager:** Rich Wells ||||  || **Project Manager:** Ethan Lilly ||   ||
 * Period covered by the report: |||||| November 15 - November 30 ||
 * **Accomplished This Period:** ||
 * * This is a way to determine the size of water heater needed: [|click here]
 * This shows the different kinds of fuel: [|click here]
 * This explains how you can use the energy factor of each unit to figure out which one is best: [|click here]
 * This is to determine the approximate annual cost: [|click here] ||
 * **Planned But Not Accomplished This Period:** ||
 * * I still need to find out what has been done in the past ||
 * **Objectives To Next Reporting Period:** ||
 * * I will find out what has been done in the past ||
 * **Risks/Outstanding Issues/Problems:** ||
 * * I need to make sure that whatever I decided works best is what will be the one that is most cost efficient for the home owner. ||

Hot Water Heater Efficiency Report

The purpose of this task was to find the best way to determine which water heater would be the best choice for any given house. This means not only the type of water heater but also the size that is needed in order to supply a sufficient amount of hot water each day. The importance of this task is that it will prevent unnecessary energy waste and in the long run save money for the house owner. This will also help Habitat for Humanity by possibly receiving a lower energy star rating on their homes. Hopefully this will slightly lower the cost of the Habitat for Humanity homes in the long run.

The main two questions that need to be answered when looking into a buying a water heater is which type will save you the most money and how much hot water do you need at any given time. A good way to figure this out is by calculating you first hour rating by using a chart such as this one:


 * Your House has: ||  ||   ||   ||
 * How many bathrooms? || 1 to 1.5 || 2 to 2.5 || 3 to 3.5 ||
 * How many bedrooms? || 1 - 2 - 3 || 2 - 3 - 4 - 5 || 3 - 4 - 5 ||
 * You need a first hour rating of: || 43-60-60 || 60-70-72-90 || 72-80-90 ||

Once you determine your first hour rating you can then look at each water heater as you shop and make sure that you buy one that is close to the capacity that you need. Next it is important to figure out which type will best suit the family. Depending on the size of the family and whether or not different hot water appliances will be used at the same time will be a major deciding point on which type of water heater to use. This chart from energystar.gov shows the four main types of water heaters and some of their pros and cons:

Water Heater Type || Energy Savings vs. Minimum Standards || Best Climates || Expected Energy Savings Over Equipment Lifetime || Expected Lifetime || Major Advantages || Storage (Tank) (Oil, Gas, Elec.) || 10% to 20% || Any || Up to $500 || 8 - 10 years || Lowest first cost || (Tankless) Using Gas or Elec. || 45% to 60% || Any || Up to $1800 || 20 years || Unlimited supply of hot water || (Compared to electric resistance) || Mild-Hot || Up to $900 || 10 years || Most efficient electric fuel option || Electric Back-Up || 70%–90% || Mild-Hot || Up to $2200 || 20 years || Largest energy savings using a renewable energy source ||
 * Comparison of Water Heaters ||  ||   ||   ||   ||   ||
 * High Efficiency
 * High Efficiency
 * Demand
 * Heat Pump || 65%
 * Solar with

This shows four different kinds of water heaters but the first two are really the only ones that are very practical for this area. There is also another energy rating number that is helpful that you can find on new water heaters. Each unit has an energy factor label that is a decimal number. The higher the number the more efficient the unit. Gas is usually between 0.5 and 0.7 while electric is 0.75 to 0.95. This is somewhat misleading however because gas is cheaper than electricity so in the end the amount of energy you save using electricity doesn't account for the price difference. It is a good idea however to try and get a unit with a good energy factor, take this chart for example:


 * Energy Factor || Energy Cost Each Year || Savings Over Life Of Appliance ||
 * 0.53 || $177 || $0 ||
 * 0.57 || $166 || $143 ||
 * 0.61 || $155 || $286 ||
 * 0.65 || $144 || $429 ||

This shows that spending more upfront will end up saving you a lot over the lifetime of the water heater, so go with the better rated unit if you have a choice.

Tankless water heaters last up to 20 years, which is about 10 years longer than storage water heaters. They only use energy when hot water is needed, so no standby energy is wasted which is why in some cases they can save up to 10 or 20 percent off of your water heating bill. They are also generally more compact if space is an issue. However, they aren't the best option for houses that have more than two people. High end gas powered models supply only 5 gallons of 90 degree water per minute while electric is even worse at only 2 gallons of 70 degree water per minute. That is not enough for large families. Also, operation of electric tankless water heaters can in some cases be more expensive because they draw more instantaneous power than storage tanks.

For future houses, the best thing to do is to look at each situation individually and decide based on the specific family which unit would be best. If the house is just for one or two people, it may be a good idea to get a tankless water heater in order to save money. Use the first hour rating and energy factor rating to help when choosing a water heater. Another thing that may need to be looked into is adding gas to homes, because although gas actually isn't quite as efficient, it is still cheaper to use the extra energy and pay for gas instead of electricity.

In conclusion, each house and family is different so there isn't a single right answer. The best thing to do is use this information to figure out what is best for each specific situation. Also, there are other ways to save a little money here and there, such as cleaning as much as possible with cold water, or buying water saving shower heads.


 * 1) // Water Heaters // Sacramento, CA: Consumer Energy Center, web site: http://www.consumerenergycenter.org/index.html, Dec. 15, 2010