How to supply power to a construction site

Recommendation points

• What are the requirements for the power supply of the site
• Construction site electrification methods
• Option 1. There is an old house on the plot
• Option 2. Temporary connection or power supply to the construction site
• Option 3. House in a partnership
• Option 4. Interaction with neighbors
• Option 5. Generators

In this article, we will consider the main methods of electrifying a construction site. We will outline the main technical and legal problems of the implementation of power supply that arise during the construction of a country house, and we will discuss rational ways to solve them.

A piece of land has been purchased, permission to build a cottage has been received, a topographic survey has been made, geological surveys have been carried out, and a house project is in hand. It’s time to get down to the most important thing. Where does the construction begin? Naturally, with summing up the main communications. Sewerage is for the future, water is needed soon, electricity is urgent. Electrification of the construction site is a top priority, since the future homeowner will need to use equipment and various tools during the construction phase, which in the overwhelming majority need power. Do not forget about the lighting of the site and the premises of the house under construction, especially in winter and in the autumn-spring period, when the daylight hours are relatively short and often cloudy. Electricity will not be superfluous for organizing the life of workers, for example, to warm up food or prepare tea. In winter and in the off-season at the facility under construction, it is necessary to ensure a positive temperature, and even if non-electric heating is implemented, 220 V power may be needed to operate volatile systems, which are now the majority. We talked about country heating in the article “Choosing the optimal system for heating a summer cottage”.

What are the requirements for the power supply of the site

There are several ways to solve the energy issue, which have their own specifics, but in any case, the electrification of the construction site should be:

• quality
• stable
• safe

All three of these points relate to the technical component. Quality should be understood as the compliance of the network parameters with the applicable standards. Voltage swings and floating frequencies have a very negative effect on the performance of tools and complex equipment. The units cannot reach the rated power, do not accelerate the working equipment to the specified speed mode and do not provide the required torque – the tool is overloaded and becomes dangerous for the user. And yet, the allocated power should simply be enough so as not to overload the network..

Stability is another cornerstone. A sudden power outage can completely paralyze a construction site. However, most importantly, they can lead to serious financial losses, for example, if only the laid concrete needs to be heated in winter or canceled pre-planned and paid activities involving contractors..

Security is hardly worth talking about in detail. It should be maximum, since the network is operated in extreme conditions at the construction site, therefore, both equipment and people need protection. Sensitive circuit breakers and high-quality RCDs should be used immediately – they will come in handy in the future. Take it for granted that the first step is to organize grounding – especially since its presence and performance will be checked in any case if everything is done according to the rules. In addition, the energy must be supplied in a quality manner to certain areas of the site: the correct section and type of cable must be used; do not operate the carrier in a twisted form; protect wires, for example by hanging them on supports; use sockets with a high level of protection against moisture and solid particles, type IP54.

There are also near-construction problems. The developer will have to delve into the legal issues of allocating capacities and supplying sites from centralized highways. In fact, there are many minefields here, you need to interact with suppliers (they also perform control functions), as well as with neighbors in the village. The legislation on the electricity supply of the population is a little vague and not all participants in the process are taken seriously, the time from application to connection is gigantic, therefore paper (and not only) wars do not subside, people offended by the authorities increasingly resort to the help of the courts.

And the last is the financial component. Unfortunately, all steps in the difficult matter of power supply of the site are paid, one might say, “very paid”, so the options “to save a little” in this matter look quite appropriate.

Construction site electrification methods

The feasibility of one or another power supply option depends on many factors. Based on technical and financial prerequisites, several electrification methods may be acceptable, and sometimes the developer has practically no choice. At the same time, the economic component dominates, since the construction site can be powered almost always and everywhere, if there was money. What can affect the cost of connection? Only the most basic:

• location of the object (distance from networks);
• the purpose of the facility under construction (dacha in SNT or a residential cottage in the village);
• permanent or temporary connection for a construction site;
• the amount of power required (you need to pay extra for each kilowatt in excess of the norm);
• 220 or 380;
• the required level of power supply reliability;
• the state of the highways to which the object can be connected, whether it is necessary to carry out modernization (replacement of the transformer substation, etc.);
• timing.

In principle, we will divide the power supply of the construction site into: stationary and autonomous. Most often, for the electrification of a construction site, a temporary or permanent connection to public networks is carried out, so we will start with it..

Option 1. There is an old house on the plot

If you are the owner of a plot with an old house, and it is connected (there is a personal account), this is the most convenient option. We are powered by it for the entire construction period. However, in the future, in order to officially connect a new house and break the old one, you will have to contact the relevant authorities. Since the connection of the power-receiving installations of individuals is carried out once, certain difficulties arise. Some developers manage to get rid of the meter transfer procedure in different ways, others first put a new house into operation, and then receive a technical specification, make a project further down the list … As a rule, new houses are larger and better equipped with consumers, therefore an increase in capacity is ordered in parallel, including including three-phase power supply. By the way, let’s determine the procedure for connecting a new house, especially since the temporary power supply of the construction site is done according to the same scenario:

1. We calculate the required load, estimate how much power is needed. Do not forget that if 15 kW is enough for you, then the connection can be made at a preferential rate – 550 rubles (if from the site to the highway no more than 500 meters in rural areas, no more than 300 meters within the city and urban settlement).
2. Obtaining technical specifications. TU is a kind of permission document from the supplying organization, which evaluates the technical capabilities to provide you with a connection point. We turn to the owners of networks in our region, put forward our wishes (how much power, what voltage, what reliability …).
3. According to the received technical specifications, a specialized organization with a license makes a project for the power supply of the house.
4. The project is coordinated with the grid organization or Rostekhnadzor.
5. Electrical work in progress.
6. Laboratory studies of the electrical network are being carried out.
7. The object is put into operation, an agreement is concluded with a sales company.

The total cost of obtaining permits, checks and approvals (we do not take into account installation, we do not apply to firms that help to do paperwork for you) in the most successful cases costs 500–1000 USD. e. For large cottages with high capacity figures in the 5-10 thousand cu. That is, it is not uncommon, since the receipt of each extra kilowatt of power is paid at a special rate. Real terms before the start of installation work are about 1–2 months, and about a month is spent on points 6 and 7. It is interesting that for the temporary connection of an individual’s construction site (power up to 15 kW), the distributors have determined the maximum terms – it can be long 6 months … The experience of practicing builders, for whom time is money, shows that if you do everything “through one window” and involve the human factor, then the technical specifications are significantly expanded, the terms of approvals are reduced significantly, electrical work can be limited to wiring in one room …

For reference: connection issues are regulated by the “Rules for Technological Connection of Power Receiving Devices of Electric Energy Consumers, Electric Power Generation Facilities, as well as Power Grid Facilities belonging to Grid Organizations and Other Persons, to Electric Grids” (approved by the Government of the Russian Federation of December 27, 2004 No. N 861 and as amended in the Decree of the Government of the Russian Federation of 04.05.2012 N 442).

Option 2. Temporary connection or power supply to the construction site

We resort to this method if you have to build “in an open field”, since it is impossible to legally connect to the power transmission line without having any buildings and personal accounts on the site. The idea is simple: first, we get a temporary power supply and calmly, without depending on anyone, we build our own house, and when it is completed, we perform the main connection. To be able to realize the power supply of the construction site, it is necessary to follow the same procedures as in the case of connecting a new house (see above), only documents accompanying the site are submitted to the regulatory authorities, and the project is drawn up for the power supply of the construction site. It should be noted that after the completion of construction, everything needs to be repeated, only it happens faster and a little cheaper, since you will already be a “registered user”.

To organize the power supply of the construction site, it is necessary to purchase a waterproof (IP54) metal box with a vandal-proof window. Many users, in addition to the standard locking devices, weld hinges to use the padlock. It is better to choose the size of the shield with a margin, so that if desired, you can use it later in the house. You should also buy a meter, one RCD and several circuit breakers – the type and rating of these devices is selected depending on the working scheme and the power provided. You will also need 220 volt sockets (1-3 pieces), which are installed on a din rail. If there is 380, then you can install a three-phase socket-connector. Do not forget about the busbars for grounding and for the neutral conductor..

The box is mounted either on a power transmission line support using clasping brackets, or on a special rack near the post. Accordingly, the power is started either from above (the wire is laid in the pipe), or from below, from the ground. According to the rules, this shield is installed at the border of the site or no more than 25 meters deep into it. Firstly, this means that the shield must be located exclusively on the applicant’s site. Secondly, this makes it possible to mount the input on the wall of some structure, which has a positive effect on the safety of the temporary ASU. For example, many contractors first of all erect on the site one of the auxiliary, detached buildings, which during the construction period serves as a gatehouse, warehouse, change house. Moreover, energy metering devices are allowed to be installed indoors. Only the consumer must undertake to provide access to the meter to representatives of the network and sales organization. Another option for internal installation is the installation of a meter with information transmission devices at a centralized data collection point, these are accounting devices with a PLC or a GSM modem. In any case, for this, you should contact the sales organization with a request to change the location of the shield (one of the points of the TU).

The allocated capacity usually depends on the Technical Conditions that are provided to the developer. It is important here how far you are from the lines, what is their condition, what is the power of the substation, how many consumers are already connected. In theory, the connection of a new facility, unless the reconstruction of the power grid facilities is carried out, should not affect the quality and reliability of electricity for already connected users. As a result, for a number of reasons, the capacity allocated by the RES is not enough either for construction or for the operation of a house (especially for increased comfort). At a construction site, of course, you can get by with generators, but then what? Therefore, it makes sense to think in advance about solving the problem. If the services of “providing additional capacity” or “increasing the existing capacity” cannot be used, then private traders sometimes resort to reconstruction of common networks at their own expense or collective efforts. In some cases, developers install their own transformer substation and receive virtually unlimited power, as well as ideal energy. In the future, connection to a personal TP can be sold to everyone.

If there are no problems with the allocated capacity, then it is better to order as much of it for the electrification of the construction site as will be needed later for the house. Taking into account the privileges for connection, up to 15 kilowatts for 550 rubles, then this figure can be safely stopped. If we talk about private cottage construction, a team of 4-5 people is unlikely to load the network by more than 5-7 kW, all the more if we take into account the energy efficiency of modern tools, the popularization of battery technology, and the use of the demand factor (not all tools and lighting devices included immediately) and power factor (not all included tools and engineering units are operating at full capacity).

Theoretically, the amount of energy consumed by one subscriber is not limited by legislation, but there are technical limitations. Therefore, sales organizations sometimes decide to install special disconnecting devices (PZR – protective relay devices), which automatically monitor the maximum power consumption. There is another way: by installing in our shields input machines of a deliberately low rating, energy suppliers limit the maximum power. Also for these purposes, meters with built-in power limiters can be used..

The temporary connection for construction has one unpleasant nuance – the cost of a kilowatt, which is determined by special tariff committees. In any case, you will have to pay more than for household electricity. The logic of power engineers is as follows: What if you are building houses for sale? For merchants – special conditions!

Option 3. House in a partnership

The collective connection of members of a non-profit (summer cottage, gardening or horticultural) association is always cheaper, since SNT is a single legal entity, and a number of financial issues are resolved by a joint. On the other hand, many partnerships were formed a long time ago and, against the background of significant problems with capacity, attempts are being made to limit the technical capabilities of newcomers who have bought a plot or, for example, inherited it. If the networks were modernized (in particular, TP and supports, wires were replaced), then newcomers are required to pay a round amount of money for the right to connect. There is nothing illegal in this, but the announced amounts are not always adequate. Sometimes beginners are offered to replace the transformer with a more powerful one at their own expense, which is illegal and often technically unreasonable. If new users appear, then the capacity is not summed up in full, since the demand coefficients are in effect. For example, for 100 summer residents (up to 15 kW per site), a 160 kilovolt transformer is needed, and for 200 it will normally be 250, not 320. By the way, any summer resident has the right to conclude an individual contract for electricity supply and pay for energy independently.

Option 4. Interaction with neighbors

As you already understood, connecting to common networks is reliable and 100% legal, but questions may arise about the timing of technical connection, or friction with the members of the association. Since we had to start building “yesterday”, a fairly effective method to power the construction site is to connect from a neighbor. Naturally, this is done with the consent of the latter, and if he has excessive power. Roughly speaking, people leave the carrier between sites, and use a counter for mutual settlements. Available power is negotiated and possibly limited to the use of PZR and similar devices in order not to create congestion in the donor’s network.

Such a system is cheap and convenient for the developer – you can intercept while the papers are being prepared, or even quickly build a house and already connect it. But this option is very much disliked by the regulatory authorities, even despite the fact that all kilowatts are paid for, and the power allocated to the officially registered consumer is not exceeded (that is, there is no threat to the village network). Firstly, they lose earnings on design work, permits and approvals (for example, for temporary power supply to a construction site), as well as on remuneration for employees in charge for “quick” connection. Secondly, the tariffs. It turns out that in fact the developer pays as for a residential property.

The consumer distributing the power runs the risk of getting into trouble from the inspectors. In fact, people are only intimidated by blackouts for changes in the power supply scheme, for unlicensed redistribution of energy, and even for illegal business. An exception is the situation if you operate your own substation and sell the right to connect, but you still need to obtain permission for this. By the way, similar friction arises in SNT when someone feeds a neighbor. Suppose a person is rarely in the country, and because of one light bulb it is unprofitable to share. The lost profit worries the activists of the non-profit association, and scandals flare up. Seasoned builders solve the problem quietly, they hide the wires, keep generators ready (sometimes they start them), in order to explain the presence of light in case of anything.

Option 5. Generators

The use of a generator is by far the best solution for reasons of autonomy. You do not depend on outages, do not need permits and approvals, the construction site will receive as many kilowatts as the workflow requires. It is very important that the generators provide the ideal voltage and frequency, alternating and, if you prefer, direct current. The only drawback of mobile power plants is the high cost of the energy received (a 10 kW diesel generator at full load burns about 3 liters of fuel per hour, a gasoline one – about four), so it is impractical to use them throughout the construction period. The generator will help the builders “move in” to the facility and perform some initial work, while the fixed connection issues are being resolved. In the future, an autonomous unit will come in handy as a power reserve (suppose, in parallel with a hand tool, it is necessary to power a welding or a pair of concrete mixers). He will also save if the light is periodically turned off in the village..

The choice of a generator is a separate topic, but we will outline a couple of points. For small volumes of work, for example, as in low-rise construction, it will be more profitable to use relatively inexpensive gasoline generators of 5-10 kW. Diesel units will pay off only with regular use or with large volumes of energy consumption, but in some situations it is worth considering the option of renting a generator. Renting a diesel engine for 30 kW will cost the developer from 2000 rubles per day, and gasoline – from 500 to 1500, depending on the power and brand.