Whether it's water, electricity, gas, or any other power source, utility companies are an essential part of everyday life. This makes them ideal for investor consideration. Let's look at three companies that would make a great addition to your watchlist. We can help you keep tabs on your investments with MyWatchlist.com, our free, personalized stock-tracking service. 

Here are three dividend stocks to consider adding to your watchlist.

The up and comer
Operating primarily in utilities, transport and energy, and timber sectors, Brookfield Infrastructure Partners (NYSE: BIP) is a relative newcomer. Since going public in 2007, Brookfield has seen its net income go from $17 million to $457 million. Pretty good, right? Let's take a closer look.

Currently, Brookfield has a dividend yield of 5.1%, while the industry average is 3.6%. Add to that a free cash flow of $78 million, interest coverage of 4.43, and a dividend that's grown 37.4% since 2009, and you're looking at a solid, growing company.

The poised for regrowth
To say that electricity and natural gas company National Grid (NYSE: NGG) has had a rough few years is an understatement. Since 2008, National Grid has seen its net income from continuing operations drop from $3.1 billion in 2008 to $2.1 billion in 2010. But is National Grid poised for a comeback?

Currently, National Grid's P/E ratio is 11.9. Compared to peers Consolidated Edison's (NYSE: ED) P/E of 14.13, Duke Energy's (NYSE: DUK) P/E of 17.85, and American Electric Power's (NYSE: AEP) of 15.27, National Grid looks like a good value. Additionally, National Grid has a dividend yield of 4.1% compared to the industry standard of 2.7%. Moreover, its free cash flow is $2.3 billion, with an interest coverage of 2.04.  

And the icing on the cake? Between 2009 and 2010, National Grid grew its dividend paid per share by 8% and increased its net income from continuing operations to $3.4 billion in 2011. Not too shabby if you ask me, and all in all, National Grid looks good by the numbers.

The not so hot?
The first time I heard of PG&E (NYSE: PCG) was when I was watching Erin Brockovich, so I have to admit I'm slightly biased against this gas and electric company. So let's let the numbers do the talking. Since 2008, PG&E has seen its net revenue fall from $1.2 billion to just under $1.1 billion. Not great, but not the worst either. Let's keep looking.

Currently, PG&E has a P/E ratio of 17.3 compared to its industry standard of 14.7. This shows that PG&E is slightly overpriced compared with its competitors. Additionally, PG&E's dividend yield is 4%, which is under the 4.3% average. The bad news keeps coming when you look at free cash flow. As of Dec. 31, 2010, PG&E had a negative cash flow of $596 million. Not good when you consider dividends get paid from free cash flow.

There are, however, two positives working for PG&E. First, it was able to raise its dividend paid per share by 8.3% since 2009, and second, its interest coverage is 3.43. So is a growing dividend enough to get me excited about PG&E's future? Maybe, but I'm going to wait and see if its P/E drops.

My Foolish bottom line
All utility companies are not created equal, but if you find one that looks good by the numbers, it'll often come with a great dividend. Add to that the fact that utility companies are a necessity -- no one wants to go back to candles and outhouses -- and you've got a company that could make a great addition to your portfolio.

Consider the three stocks above along with the 13 names in a free report from Motley Fool expert analysts, "13 High-Yielding Stocks to Buy Today." A senior retail analyst dubbed one of the picks "the dividend play of a lifetime." Tens of thousands have requested access to this report, and today I invite you to download it at no cost. To get instant access to the names of these 13 high yielders, simply click here -- it's free.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.