It's advisable to hire a licensed electrician to run power to your shed. While doing it yourself may be cheaper, it can be dangerous and requires permits to ensure legality.
You can't just plug in the shed to an exterior outlet. At a minimum you need a new circuit with a breaker, cable buried, ideally in conduit. Done correctly for what you are describing, your shed would need a small breaker panel with a circuit for the AC and circuit(s) for the outlets.
The cost to run electricity to a shed or detached garage costs $10 to $25 per linear foot of underground line, or an average of $2,500. Prices typically range from $1,000 to $3,800.
How much does it cost to wire a 30×40 shop? When planning your new shop's electrical wiring, consider labor rates, wiring complexity, distance from the existing electrical service, and materials used. Expect to pay roughly $3 to $7 per square foot, totaling $3,600 to $8,400 for a 30x40 shop.
You'll be fine with the extension cord. I recommend that you wire the shed up properly internally and run a nice robust cord to a waterproof external port.
We would always recommend a 32A 30mA RCD Protected Supply for our garden buildings. A 6mm SWA Cable would normally be large enough pending the length of cable run.
The electrical supply to your shed needs to run from your main property. You may be able to connect it your existing fuse box. But if this fuse box is old, then you may need a new fuse box to accommodate the new power draw. Obviously, this will cost more, so you may need to work it into your budget.
Just as described before, the wire will have to be matched with the amount of voltage it can safely carry. For a 20 Amp circuit traveling 25' or less, a 12/2 with ground (yellow) will suffice. If that same 20 Amp circuit must travel more like 150 feet, the cable would have to be #6 gauge or larger.
Wire a Garage
Adding circuits to a garage ranges from $1,200 to $2,500. With a detached garage, an underground feeder cable must be installed to supply a new circuit. Installing a 240-volt receptacle and a level 2 charger for recharging an electric car can cost as much as $4,800.
Most spend between $900 and $1,300. Adding plumbing to a detached garage or shed roughly 20 feet away from home will cost $1,100 for the average homeowner. Homeowners pay between $900 and $1,300 just to run the lines when adding plumbing to a shed or detached garage.
Cost and Process for Installing Permanent Power
The cost of installing power is heavily dependent upon the process and location, but in most cases, you should expect to spend $10,000 or more. Most utility companies will charge you for every foot they have to extend a line to your property and on your property.
The cost to run electricity to a shed, garage, or shop is $10 to $25 per linear foot or $500 to $3,800 on average for 50 to 150 feet of underground line. The average cost to run electric to a detached building and wire the interior is $1,200 to $7,100.
These options include solar power, underground wiring like SWA cable, overhead wiring, and using an extension lead from your house. Solar power emerges as an environmentally friendly choice for powering your garden shed.
You can usually do your own electrical work as long as it is done for yourself, not commercially. Other conditions may apply, too. You may need to show a house deed to prove that you are the owner. You may need to take a brief examination to gain a temporary license to perform the work.
UF cable is a popular choice when designing an underground run to feed a sub-panel in a shed or anywhere else. UF stands for underground feed. It doesn't need to be protected with PVC conduit or any code-compliant mechanical protection, as it covers all the requirements on its own.
The rule of volt drop is as follows: the drop in voltage on the circuit should not exceed five percent. If you're using 12-gauge wire on a 20 amp power load, that means you can run the circuit almost as long as 57 feet without experiencing more than a five percent volt drop.
This means that for 500 feet, the cost can range from $2500 to $10,000. When adding up all the costs involved in running power lines for a distance of 500 feet, the estimated total can range from $6300 to $37,500, depending on the specific requirements and location.
The THWN wire meaning is short for Thermoplastic High Water-resistant Nylon-coated. In THHN, water is replaced with heat.
Your choice primarily depends on the type of soil you have. If it's granular and easy to dig, you can save money on electrical materials by digging deep; you may not need to install metal or plastic conduit to protect the buried wiring from physical damage.
However, leaving exposed wires running along the outside of a home or building is never a safe idea. To protect these wires from the elements, many owners elect to run them through an exterior wall with a conduit for an added layer of protection and simplified installation.
Cable Above the Ground
Cable above ground is a cheaper option. Its installation is hassle-free and provides a permanent power source. Install these cables when a certain distance lies between your shed and the main house.
The answer is that it can be acceptable to run an extension cable to a shed, but only on a temporary and short-term basis. If you are seeking a long-term solution, then you will need to go down the route of a professional power installation.