user2229: What's the hash power requirements to solo mine and win at least one block a day?
Two cases (with 10% luck, means mining requires to iterate 90% of unsuccessful hashes), 

Mine 24 hours a day and win at least one block
Mine 10 - 30 mins and win at least one block


user516: The following is assuming the difficulty has balanced with the current network hash rate (right now, the difficulty is actually about 10% low, but it will adjust in about 3 days):
Network hash rate (current) = 61 Thash/s
Blocks per day = 24 * 6 = 144
Hash power required to solve 1 block per day = 61 Thash/s / 144 = 424 Ghash/s
To get a block on average every 30 minutes, you'd need control of one third of the network's hashpower, which (unless you purchase mining equipment already in use) would require 50% of the current hashpower, or 30.5 Thash/s. 
To solve a block on average every 10 minutes is only possible if you control the entire network, which you can't do unless you stop everybody else from mining.
More info available here: Equation for mining profit

user1097: You can mine 1 block roughly every 10 mins, hence total blocks per day is 6 x 24 = 144
The current Hash Rate in the Network is about 70000 GH/sec (Source: Blockchain.info]1
If you have 100% of the Hash power, you will get all the blocks each day.
To get at least one block a day, you will need roughly 0.7% of the current total hash power (1/144), that is about 486 GH/sec of hash power.
To get at least one coin a day, you will need at least 19.44GH/sec of hash power ( 486 / 25 coins per block)
The hash power requirement will change as the network hash rate rises with more ASIC devices shipped.

2229: <p>What's the hash power requirements to solo mine and win at least one block a day?</p>

<p>Two cases (with 10% luck, means mining requires to iterate 90% of unsuccessful hashes), </p>

<ol>
<li>Mine 24 hours a day and win at least one block</li>
<li>Mine 10 - 30 mins and win at least one block</li>
</ol>
 516: <p>The following is assuming the difficulty has balanced with the current network hash rate (right now, the difficulty is actually about 10% low, but it will adjust in about 3 days):</p>

<p>Network hash rate (current) = 61 Thash/s</p>

<p>Blocks per day = 24 * 6 = 144</p>

<p>Hash power required to solve 1 block per day = 61 Thash/s / 144 = 424 Ghash/s</p>

<p>To get a block on average every 30 minutes, you'd need control of one third of the network's hashpower, which (unless you purchase mining equipment already in use) would require 50% of the current hashpower, or 30.5 Thash/s. </p>

<p>To solve a block on average every 10 minutes is only possible if you control the entire network, which you can't do unless you stop everybody else from mining.</p>

<p>More info available here: <a href="https://bitcoin.stackexchange.com/questions/8568/equation-for-mining-profit">Equation for mining profit</a></p>
 1097: <p>You can mine 1 block roughly every 10 mins, hence total blocks per day is 6 x 24 = 144</p>

<p>The current Hash Rate in the Network is about 70000 GH/sec (Source: Blockchain.info]<a href="http://blockchain.info/charts/hash-rate" rel="nofollow">1</a></p>

<p>If you have 100% of the Hash power, you will get all the blocks each day.</p>

<p>To get at least one block a day, you will need roughly 0.7% of the current total hash power (1/144), that is about 486 GH/sec of hash power.</p>

<p>To get at least one coin a day, you will need at least 19.44GH/sec of hash power ( 486 / 25 coins per block)</p>

<p>The hash power requirement will change as the network hash rate rises with more ASIC devices shipped.</p>
