Pros and Cons of Newest Water Heaters
Thursday, June 14, 2007
Q. One of my neighbors just had an instantaneous water heater installed in her house and she loves it. She says the salesman told her that it will save them a lot of money on their energy bills because it is so efficient. Are they that good?
A. The good news is that these appliances are growing in popularity because they are more energy-efficient than a standard home water heater. But the bad news is that they are growing in popularity ...
First, the good. Instantaneous (also called "demand" or "tankless" water heaters) have been around for a long time, especially in hot climates where they work most efficiently, and they do offer some significant advantages over conventional water heaters with tanks.
Their biggest benefit is that they don't heat the water until it is needed, so there are no heat losses from a storage tank (traditional water heaters operate occasionally to maintain the desired temperature level even when you are not turning on the faucet). Even the best water heater tanks lose heat into the air around them and turn on once in a while to reheat cooler water.
Browse through some of the web sites of companies selling these products and you'll see some pretty strong claims for big energy savings, many claiming as much as a 60 percent savings or even more.
Regardless of how much the actual savings are, they have other benefits beyond the economic. The units are fairly small in size so they take up much less room than a water heater and can be installed just about anywhere. They can also be used to resolve some problems homeowners have with traditional water heaters.
For example, you may have a bathroom at one end of your home that is on the other side of the house from the water tank, and the water never seems to get very hot there. You can put one of these units close to that bathroom and you'll have the hot water you want much quicker. And while these units do have some limits as to how much hot water they can provide at one time, you can install two or more together to give enough hot water for showers, dish washing and other uses all at the same time.
They are more expensive than buying a gas or electric water storage tank, but the savings may pay for that increase over time.
But like I said, there's a problem with the growing popularity of the electric units (that doesn't affect the use of gas ones). I talked with some people who work for utility companies and it seemed that the electric tankless water heaters have such a high demand for electricity that rather than being a nice, neat energy-saver, they actually have very large power demands. This can cause some problems for both the homeowner and the utility company.
Homeowners often find right from the start that the wiring in their home isn't suitable to meet the electrical demand when these units are used, a demand that can reach 30,000 watts or even more (compare this to the 4,500-watt demand of a conventional electric water heater). That can mean electrical work to upgrade the electrical circuits in the home, possibly even requiring a separate electrical panel and new wiring, costs that can run into the hundreds and even thousands of dollars and costs that will be borne by the homeowner, not the utility.
But the utility is going to need more heavy-duty wires, meters, transformers and other equipment for the spikes in generation they've got to meet. And at some utilities these costs are going to get paid through increases in all of the electric rates over time. At other utilities, the entire cost of these upgrades is charged directly to the customer who purchases the high demand electric water heater.
So my recommendations are that you learn as much as you can about instantaneous water heaters (there are lots of great web sites and many companies selling them), and think about your home's hot water needs. If you find that this product would work well for you, next contact your local utility before committing to any purchase. And please consider the gas rather than electric units to avoid creating a problem for utilities that will only get worse as more of the units are used.
http://www.theledger.com/apps/pbcs.dll/article?AID=/20070609/NEWS/706090305/1001/BUSINESS
A. The good news is that these appliances are growing in popularity because they are more energy-efficient than a standard home water heater. But the bad news is that they are growing in popularity ...
First, the good. Instantaneous (also called "demand" or "tankless" water heaters) have been around for a long time, especially in hot climates where they work most efficiently, and they do offer some significant advantages over conventional water heaters with tanks.
Their biggest benefit is that they don't heat the water until it is needed, so there are no heat losses from a storage tank (traditional water heaters operate occasionally to maintain the desired temperature level even when you are not turning on the faucet). Even the best water heater tanks lose heat into the air around them and turn on once in a while to reheat cooler water.
Browse through some of the web sites of companies selling these products and you'll see some pretty strong claims for big energy savings, many claiming as much as a 60 percent savings or even more.
Regardless of how much the actual savings are, they have other benefits beyond the economic. The units are fairly small in size so they take up much less room than a water heater and can be installed just about anywhere. They can also be used to resolve some problems homeowners have with traditional water heaters.
For example, you may have a bathroom at one end of your home that is on the other side of the house from the water tank, and the water never seems to get very hot there. You can put one of these units close to that bathroom and you'll have the hot water you want much quicker. And while these units do have some limits as to how much hot water they can provide at one time, you can install two or more together to give enough hot water for showers, dish washing and other uses all at the same time.
They are more expensive than buying a gas or electric water storage tank, but the savings may pay for that increase over time.
But like I said, there's a problem with the growing popularity of the electric units (that doesn't affect the use of gas ones). I talked with some people who work for utility companies and it seemed that the electric tankless water heaters have such a high demand for electricity that rather than being a nice, neat energy-saver, they actually have very large power demands. This can cause some problems for both the homeowner and the utility company.
Homeowners often find right from the start that the wiring in their home isn't suitable to meet the electrical demand when these units are used, a demand that can reach 30,000 watts or even more (compare this to the 4,500-watt demand of a conventional electric water heater). That can mean electrical work to upgrade the electrical circuits in the home, possibly even requiring a separate electrical panel and new wiring, costs that can run into the hundreds and even thousands of dollars and costs that will be borne by the homeowner, not the utility.
But the utility is going to need more heavy-duty wires, meters, transformers and other equipment for the spikes in generation they've got to meet. And at some utilities these costs are going to get paid through increases in all of the electric rates over time. At other utilities, the entire cost of these upgrades is charged directly to the customer who purchases the high demand electric water heater.
So my recommendations are that you learn as much as you can about instantaneous water heaters (there are lots of great web sites and many companies selling them), and think about your home's hot water needs. If you find that this product would work well for you, next contact your local utility before committing to any purchase. And please consider the gas rather than electric units to avoid creating a problem for utilities that will only get worse as more of the units are used.
http://www.theledger.com/apps/pbcs.dll/article?AID=/20070609/NEWS/706090305/1001/BUSINESS
Labels: demand water heater, green, tankless water heater, water heater
1 Comments:
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Zakir Hosen, December 8, 2016 at 5:25 AM
Zakir Hosen, December 8, 2016 at 5:25 AM